Genetics of amylose content in rice (Oryza sativa L)

Inheritance of amylose content was studied in crosses involving very low-, intermediate-, and high-amylose parents. The single-grain analysis of parents, F₁, F₂, B₁F₁, and B₂F₁ seed from a single-season harvest, showed that the parental mean difference of 14–17 % in IR37307-8/BPI 121-407 or IR37307-8/IR24632-34 and about 20% in the cross IR37307-8/IR8 were controlled by a single gene with major effect, along with some minor genes and/or modifiers. The appearance of segregants inbetween the two parents was attributed to gene dosage effects in the endosperm. The results indicate that selection for amylose level can effectively be done in early segregating generations. Selection for intermediary segregants would be ineffective because the dosage effects would dissipate in further generations.     

Chromosomal location of genes conditioning low amylose content of endosperm starches in rice,Oryza sativa L.

Summary Eight dull mutants that lower the amylose content of rice endosperm as well as waxy mutant and a cultivar with common grains were crossed in a diallele manner. The amylose content of F₁ and F₂ seeds was determined on the basis of single grain analysis. It was concluded that the low amylose content of dull mutants is under monogenic recessive control. Alleles for low amylose content are located at five loci designated as du-1, du-2, du-3, du-4 and du-5. These loci are independent of wx locus located on chromosome 6. The five du loci have an additive effect in lowering the amylose content. Two loci, du-1 and du-4, were found to be located on chromosomes 7 and 4, respectively.     

Molecular characterization of spontaneous and induced mutations in the three homoeologous waxy genes of Japanese barnyard millet [Echinochloa esculenta (A. Braun) H. Scholz]

Japanese barnyard millet is an important food source in East Asian countries. However its crumbly texture limits desirability and consumption. Controlling amylose level in the endosperm is important to improve the eating quality of the millet. Because it is well known that the waxy gene determines the amylose level in the endosperm, we conducted a molecular analysis of the gene. Segregation analysis revealed that wild-type cultivars had three functional genes while low-amylose cultivars had one. We determined complete sequences of the three homoeologous waxy structural genes, EeWx1, EeWx2 and EeWx3, in a wild-type cultivar. These sequences showed high homology in the exon regions (97 %), and lower homology in the introns (82 %). Two spontaneous mutations were characterized in the low-amylose cultivars. In addition, one induced mutation was found in the fully waxy cultivar, Chojuromochi. Spontaneous mutations are deletions of whole and terminal regions in the EeWx2 and EeWx3 alleles, respectively. The induced mutation is a single-base deletion that led to a premature termination codon in EeWx1. These findings led us to develop useful markers for selecting low-amylose and waxy lines in millet.     

Linked epistasis for six quantitative traits in Indian mustard (Brassica juncea (L.) Czern & Coss)

Summary Gene effects, and interactions, and associations between days-to-flower initiation and maturity, number of secondary branches and siliquae per plant, and 1,000-seed weight and yield per plant were studied in a cross of Indian mustard (Brassica juncea (L.) Czern & Coss) using the parents and F₁, F₂, F₃, B₁, B₂, B₁₁, B₁₂, B₂₁, B₂₂, B_1S, B_2S, B₁F₁, B₂F₁, B_1bip, B_2bip, F₂P₁, F₂F₁, and F_2bip generations. A linked digenic model was adequate for all characters studied. According to this model, the main effects, additive and interactions between linked pairs of genes, were present in varying proportions for days-to-flower initiation and maturity and number of siliquae per plant. The contribution of linked epistatic effects, however, was much greater than that of additive effects. Dominance effects contributed significantly to the inheritance of days-to-flower initiation. Duplicate epistasis was observed for all traits except 1,000-seed weight where epistasis was of the complementary type. A complete association among the genes of similar effect (increasing or decreasing) was observed for number of secondary branches and siliquae, and yield per plant. Coupling phase linkage was observed for days-to-flower initiation whereas repulsion phase linkage was observed for daysto-maturity and 1,000-seed weight.     

The falcifolia syndrome of Oenothera: III. The general pattern of its non-Mendelian inheritance

Summary The falcifolia (fal) syndrome is a malformation characterized by shoot sectors with sickle-shaped leaves, which appears in hybrids between Oenothera suaveolens and O. lamarckiana and shows a non-chromosomal inheritance of a previously undescribed type. The determinants, their location in the cell, and the mechanism of their expression are unknown. The defect is the result of a cross in which mixing of two different cytoplasms occurs, without the usual predominantly maternal inheritance. F₁ progeny of reciprocal crosses show a quantitative difference in the frequency and degree of expression of the fal character. When the F₁ progeny are backcrossed to the parents, the percentage of fal is high in crosses to O. suaveolens and low in those to O. lamarckiana. This manner of transmission is observed regardless of whether the hybrid is used as seed or pollen parent or shows a normal or fal phenotype. F₂ generations from F₁ plants having either a normal or a fal phenotype always include a certain percentage of fal plants, although the latter generally produce a higher percentage of fal progeny. If a second backcross is carried out, plants that produce normal progeny on self-pollination behave differently from those that produce some fal off-spring when selfed. The latter are similar to the F₁ with regard to the transmission of the fal trait. Plants of the F₁B₁ yielding normal progeny upon selfing produce normal progeny in the F₁B₂ if the parent to which they are backcrossed is the same as in the first backcross; if the parents of the first and second backcross differ, a high percentage of fal offspring is obtained. Again, whether the hybrid is used as seed or pollen parent is not relevant. Exceptions to this behaviour have been observed only rarely in that the character of the penultimate cross is retained. There is some evidence of somatic segregation of the fal determinants, since sister plants may react differently; this suggestion is supported by comparing the progenies of different branches of a self-pollinated fal plant of the F₁ generation.Abbreviations F₁, F₂, F₃, F₄ First through fourth filial generation, obtained by self-pollination - F₁B₁ First backcross generation, i.e. the F₁ was backcrossed to one of the original parents - F₁B₂ Second backcross generation, i.e. the F₁B₁ was backcrossed to one of the original parents - F₁B₃ Third backcross generation, i.e. the F₁B₂ was backcrossed to one of the original parents - (F₁B₁)D₁ Descendants obtained by self-pollination of a F₁B₁ plant; further generations obtained by self-pollination are designated as D₂, D₃, D₄ - (F₁B₁)D₁B₁ Descendant or generation obtained by a backcross of the D₁ of an F₁B₁. Backcrosses of the D₂ and D₃ are designated mutatis mutandis - (F₁B₁)D₁B₂ Generation obtained by a backcross of the (F₁B₁)D₁B₁     

The altered pattern of amylose accumulation in the endosperm of low-amylose barley cultivars is attributable to a single mutant allele of granule-bound starch synthase I with a deletion in the 5'-non-coding region

Reasons for the variable amylose content of endosperm starch from waxy cultivars of barley (Hordeum vulgare) were investigated. The mature grains of most such cultivars contain some amylose, although amounts are much lower than in wild-type cultivars. In these low-amylose cultivars, amylose synthesis starts relatively late in grain development. Starch granules in the outer cell layers of the endosperm contain more amylose than those in the center. This distribution corresponds to that of granule-bound starch synthase I (GBSSI), which is more severely reduced in amount in the center of the endosperm than in the outer cell layers, relative to wild-type cultivars. A second GBSSI in the barley plant, GBSSIb, is not detectable in the endosperm and cannot account for amylose synthesis in the low-amylose cultivars. The change in the expression of GBSSI in the endosperm of the low-amylose cultivars appears to be due to a 413-bp deletion of part of the promoter and 5'-untranslated region of the gene. Although these cultivars are of diverse geographical origin, all carry this same deletion, suggesting that the low-amylose cultivars have a common waxy ancestor. Records suggest a probable source in China, first recorded in the 16th century. Two further families of waxy cultivars have no detectable amylose in the endosperm starch. These amylose-free cultivars were selected in the 20th century from chemically mutagenized populations of wild-type barley. In both cases, 1-bp alterations in the GBSSI gene completely eliminate GBSSI activity.     

Diverse origins of waxy foxtail millet crops in East and Southeast Asia mediated by multiple transposable element insertions

The naturally occurring waxy and low-amylose variants of foxtail millet and other cereals, like rice and barley, originated in East and Southeast Asia under human selection for sticky foods. Mutations in the GBSS1 gene for granule-bound starch synthase 1 are known to be associated with these traits. We have analyzed the gene in foxtail millet, and found that, in this species, these traits were originated by multiple independent insertions of transposable elements and by subsequent secondary insertions into these elements or deletion of parts of the elements. The structural analysis of transposable elements inserted in the GBSS1 gene revealed that the non-waxy was converted to the low-amylose phenotype once, while shifts from non-waxy to waxy occurred three times, from low amylose to waxy once and from waxy to low amylose once. The present results, and the geographical distribution of different waxy molecular types, strongly suggest that these types originated independently and were dispersed into their current distribution areas. The patterns of GBSS1 variation revealed here suggest that foxtail millet may serve as a key to solving the mystery of the origin of waxy-type cereals in Asia. The GBSS1 gene in foxtail millet provides a new example of the evolution of a gene involved in the processes of domestication and its post-domestication fate under the influence of human selection. Electronic Supplementary Material Supplementary material is available for this article at     

The molecular basis of mutations at the Waxy locus from Amaranthus caudatus L.: evolution of the waxy phenotype in three species of grain amaranth

Polymorphisms at the Waxy locus of Amaranthus caudatus L. collected from a wide range of regions were used to investigate genetic diversity and mutation sites. A comparison of the Waxy locus revealed a very high level of sequence conservation. This result clearly showed low environmental and evolutionary variability in the Waxy gene. We also performed screening to confirm the mutation sites in the coding sequences of all accessions. The results indicate that one insertion in the coding region of Waxy genes was responsible for the change in perisperm starch leading to the waxy phenotype in all accessions of this species, and thus that a single mutation event altered the regulation of the Waxy gene during the domestication of this crop. In addition, phylogenetic analysis showed that waxy phenotypes within each of three species, A. caudatus, A. cruentus and A. hypochondriacus, originated separately or differentiated from nonwaxy phenotypes of each species through a single mutational event (i.e., a frame shift or base substitution). We also compared obvious structural features of the coding sequence of waxy and nonwaxy phenotypes with those of low-amylose phenotypes in A. caudatus. The Waxy coding sequences of low-amylose phenotypes do not show polymorphisms and are identical with those of waxy phenotypes. This could mean that there is another gene that encodes a key enzyme responsible for amylose synthesis as the elementary quantity in tissues other than perisperm in A. caudatus.     

Genetics of gel consistency in rice (Oryza sativa L.)

Inheritance of gel consistency in rice was studied in crossés involving highamylose, low-gelatinizalion temperature parents with hard, medium, and soft gel consistency. The results of single-grain analysis of parents, F₁, F₂, B₁F₁, B₂F₂, and their reciprocal crosses from a single-season harvest showed that the differences between hard and soft, hard and medium, and medium and soft gel consistency are under monogenic control and that modifiers affect the expression of the trait. Multiple alleles at the same locus, hereby designated asgec ^a for medium gel consistency andgec ^b for soft gel consistency, were recessive to the wild type allele for hard gel consistency andgec ^a was dominant overgec ^b. The results indicate that selection for desired gel consistency can effectively be done in early segregating generations.     

The effect of acute hypoxia on prostaglandin release in perfused human fetal placenta

The release of prostaglandin E₂ and F_2α, thromboxane B₂ and 6-keto-prostaglandin F_1α was measured in isolated human placental cotyledons perfused under high- and low-oxygen conditions. Also the effect of reoxygenation on prostaglandin production was studied. During the high-oxygen period, prostaglandin E₂ accounted for 44 % and 6-keto-prostaglandin F_1α for 28 % of all prostaglandin release, and the rank order of prostaglandin release was E₂ > 6-keto-prostaglandin F_1α > thromboxane B₂ > prostaglandin F_2α. Hypoxia had no significant effect on quantitative prostaglandin release, but the ration of prostaglandin E₂ to prostaglandin F_2α was significantly increased. After the hypoxic period during reoxygenation the release of 6-keto-prostaglandin F_1α was significantly decreased, as was the ratio of 6-keto-prostaglandin F_1α to thromboxane B₂. Also the ratio of the vasodilating prostaglandins (E₂, 6-keto-prostaglandin F_1α) to the vasocontricting prostaglandins (thromboxane B₂, prostaglandin F_2α) was decreased during reoxygenation period. With the constant flow rate, the perfusion pressure increased during hypoxia in six and was unchanged in three preparation. The results indicate that changes in the tissue oxygenation in the placenta affect prostaglandin release in the fetal placental circulation. This may also have circulatory consequences.     

Quantitative genetics of growth and development in Populus. I. A three-generation comparison of tree architecture during the first 2 years of growth

One approach to gain an insight into the genetics of tree architecture is to make use of morphologically divergent parents and study their segregating progeny in the F₂ and backcross (B₁) generations. This approach was chosen in the present study in which material of a three-generation pedigree growing side by side in a replicated plantation, was analyzed. The pedigree included Populus trichocarpa (T) and P. deltoides (D) parents, their F₁ and F₂ hybrids and their B₁ hybrids to the D parent. The trees were grown in the environment of the T parent and measured for the first 2 years of growth. Nine quantitative traits were studied at the stem, branch and leaf levels of tree architecture, in which the original parents differed. Strong F₁ hybrid vigor relative to the better parent (T) was expressed in growth and its components. Most quantitative traits in the F₂ and B₁ hybrids were intermediate between the T and D parents but displayed a wide range of variation due to segregation. The results from the analysis of variance indicated that all morphometric traits were significantly different among F₂ and B₁ clones, but the B₁ hybrids were more sensitive to replicates than the F₂. Broad-sense heritabilities (H ²) based on clonal means ranged from moderately high to high (0.50–0.90) for the traits studied, with H ² values varying over age. The H ² estimates reflected greater environmental noise in the B₁ than in the F₂, presumably due to the greater proportion of maladaptive D alleles in those hybrids. In both families, sylleptic branch number and length, and leaf size on the terminal, showed strong genetic correlations with stem growth. The large divergence between the two original parents in the traits studied, combined with the high chromosome number in Populus (2n=38), makes this pedigree well suited for the estimation of the number of quantitative trait loci (QTLs) underlying quantitative variation by Wright's biometric method (1968). Variation in several traits was found to be under the control of surprisingly few major QTLs: 3–4 in 2nd-year height and diameter growth, a single QTL in stem diameter/height ratio.     

Effects of selective destruction of iron-sulfur center B on electron transfer and charge recombination in Photosystem I

Incubation of spinach thylakoids with HgCl₂ selectively destroys Fe–S center B (F_B). The function of electron acceptors in F_B-less PS I particles was studied by following the decay kinetics of P700⁺ at room temperature after multiple flash excitation in the absence of a terminal electron acceptor. In untreated particles, the decay kinetics of the signal after the first and the second flashes were very similar (t _1/22.5 ms), and were principally determined by the concentration of the artificial electron donor added. The decay after the third flash was fast (t _1/20.25 ms). In F_B-less particles, although the decay after the first flash was slow, fast decay was observed already after the second flash. We conclude that in F_B-less particles, electron transfer can proceed normally at room temperature from F_X to F_A and that the charge recombination between P700⁺ and F_X ^-/A₁ ^- predominated after the second excitation. The rate of this recombination process is not significantly affected by the destruction of F_B. Even in the presence of 60% glycerol, F_B-less particles can transfer electrons to F_A at room temperature as efficiently as untreated particles.Abbreviations DCIP 2, 6-dichlorophenol indophenol - F_A, F_B, F_X iron-sulfur center A, B and X, respectively - PMS phenazine methosulfate     

Genetic studies of rice (Oryza sativa L.) anther culture response

Anthers of two rice (Oryza sativa L.) varieties, Lunhui 422 (P₁) and Jinzao 5 (P₂), their F₁, F₂ and first backcross generation-F₁ x Lunhui 422 (B₁), and F₁ x Jinzao 5 (B₂)-were cultured in L8 medium to study the inheritance of rice anther culturability using generation mean analysis. Significant effects of generation were observed for the four traits measured: anther response (%), frequency of callus induction (%), frequency of callus differentiation (%) and culture efficiency (%). Variation among the generations was similar for all traits: significant differences were found among six generations and the means of the P₂ and B₂ were significantly lower than those of the other generations. The frequency of callus differentiation showed a nonsignificant difference among the P₁, F₁, F₂ and B₁ generations which had slightly high values than the P₂ and B₂. Additive genetic variance (V_A) was higher than non-additive genetic variance (V_D) for anther response and frequency of callus induction. However, A_V was lower than V_D for frequence of callus differentiation and culture efficiency, V_A was significant for all traits except for the culture efficiency, and V_D was nonsignificant for all traits except for the frequency of callus differentiation. On the other hand, environmental variation (V_E) was significant for the 4 traits. Narrow-sense heritability estimates were 95.52%, 82.19% and 13.54% for anther response, frequency of callus induction and culture efficiency, respectively.Abbreviations 2,4-d 2,4-dichlorophenoxyacetic acid - IAA indole-3-acetic acid     

Genetic analysis of the duplicate loci,cluster and short branch in Gossypium hirsutum L.

Summary Six generations, namely P₁, P₂, F₁, F₂, B₁ and B₂, of five different crosses involving diverse parents, H14 (Local standard), Res H141 (Reselection of H141), 419/49 (Punjab), 5143C (Ceylon) and Banda-I (Africa) on one hand and PRS-72 a cluster type strain on the other, were studied to gain understanding of the genetics of short fruiting branch and cluster boll bearing in upland cotton, Gossypium hirsutum L. Observations were recorded on cluster vs. noncluster normal plants in the first and second filial and B₁ and B₂ generations. The segregation ratios of cluster: normal boll bearing in the F₂ and B₂ (test cross) progenies confirmed that the character is monogenic recessive (cl₁cl₁) in inheritance. Though the penetrance of the gene which controlled cluster boll bearing was complete, its expression varied. As many as 15 different types of cluster have been described. Length of cluster bearing sympods varied. On average the sympod lengths in PRS-72 and the cluster type F₂ and B₂ were 2.13 and 4.54 cm, respectively, suggesting influence of specific modifiers evolved in the cluster donor parent and the different genetic backgrounds. It was suggested that there is a dosage effect of modifiers and interaction of homeologous duplicate allele (Cl₂ Cl₂) in governing the length of the cluster bearing sympods.Part of the thesis submitted to the Punjab Agricultural University in partial fulfilment of requirements for the degree of Doctor of Philosophy (Genetics) by the senior author.     

Mutation loci and intragenic selection marker of the granule-bound starch synthase gene in waxy maize

Four pairs of specific PCR primers have been designed on the basis of the sequence of the granule-bound starch synthase gene (GBSS; dominant non-waxy gene Wx) and used to amplify its homologous sequence from thirteen waxy and two non-waxy inbred lines. Results from electrophoresis indicated that the recessive waxy gene was wx, derived from the dominant non-waxy gene Wx by mutation at its 3′ end. The sequence of the mutated 3′ end was amplified by the TAIL-PCR technique. Sequence alignment showed that the mutation of the wx gene was caused by transposition of the aldehyde dehydrogenase gene rf2. Two pairs of specific primers were designed on the basis of the sequence difference between the dominant gene Wx and its mutated recessive allele wx and used as intragenic selection markers to identify individual plants of genotypes WxWx, Wxwx, and wxwx by PCR amplification from the segregating population of the F₂ generation crossed between waxy and non-waxy inbred lines. Iodine solution staining and starch component assay showed that all the 35 F₂ plants identified as genotype WxWx produced non-waxy kernels of the F₃ generation and that all 33 F₂ plants identified as genotype wxwx produced waxy kernels of the F₃ generation. This result can be used to improve the selection efficiency of waxy maize breeding and for selection of other single genes and major polygenes.     

Genetic control of grain yield and its related traits in bread wheat

Summary Genetic control of tiller number, grain number, grain weight, harvest index and grain yield in six generations, along with the biparentals, F₃s, F₂xparental progeny, and F₂xF₁ progeny were investigated in an intervarietal cross of bread wheat involving two highly competitive varieties, WL711 and HD 2009. The performance of F₁, B₁, B₂, F₂, × p₁, F₂ × P₂ and F₂ × F₁ progeny was midway between the parents involved with respect to all the evaluated characters. The biparental progeny excelled the mean performance of their corresponding F₂ and F₃ progeny in tiller number, seed weight and grain yield. The estimates of variance components obtained from the two models deployed were almost similar. Considerable additive genetic variance was observed for grains per spike, seed weight and grain yield while dominance variance was more pronounced for harvest index. The additive-dominance model was adequate for grains per spike and harvest index. Epistatic effects of additive × additive and additive × dominance type for tiller number and grain yield, and of additive × dominance type for seed weight were observed. The digenic epistatic model was inadequate for explaining the nature of gene action for tiller number, seed weight and grain yield. The studies indicated that non-allelic interactions should not be ignored in formulating wheat breeding programmes and that a biparental approach could be adopted as an extremely useful tool for enhancing genetic variability and the creation of transgressive segregants. The usefulness of breeding methodologies utilising a biparental approach is discussed.     

超甜玉米种子萌发物质利用性状杂种优势及亲子回归关系分析

为阐明超甜玉米(Zea mays L.var.saccharata Bailey)亲本对F_1种子物质利用性状遗传效应,研究了19份自交系和其测配的10个杂交组合的杂种优势及亲子回归关系。结果表明,超甜玉米自交系及F_1种子的淀粉含量、蛋白质含量、脂肪含量、百粒重、种子物质动用量和种子物质利用率差异较大,10个杂交组合中亲本和F_1种子的淀粉含量、脂肪含量、百粒重均存在显著差异。F_1种子淀粉含量和百粒重均表现出正向超亲优势,即近高亲本遗传;而F_1种子的蛋白质含量、脂肪含量、种子物质动用量和种子物质利用率为近低亲本遗传。聚类分析和杂种优势分析表明,性状差异较大的FH14、Q26、GT22、GT2等亲本测配的杂交组合在种子百粒重或种子物质利用率等性状上具有较强的超亲优势。回归分析表明,母本对F_1种子的淀粉含量、百粒重有负效应,对种子物质动用量和种子物质利用率有正效应;父本对种子淀粉含量有负效应,对种子物质利用率有正效应。     

Genetic analysis of Verticillium wilt tolerance in cotton using pedigree data from three crosses

Summary Three crosses and descendant generations were used in a field study of the inheritance of tolerance to Verticillium wilt, caused by Verticillium dahliae Kleb., in upland cotton (Gossypium hirsutum L.). The tolerant cultivar Acala SJC-1 was crossed to more susceptible parents, breeding line S5971 and cultivars Acala 4-42 and Deltapine 70. Seven generations were evaluated for each cross: the two parents (P₁ and P₂), F₁; F₂, F₃, and reciprocal backcrosses (B₁ and B₂). The genetic control of tolerance in these crosses appears to involve more than one gene, based on an unsatisfactory fit to expected phenotypic distributions for the generations under a single-locus model. An analysis of generation means indicated that pooled additive and pooled dominance effects over loci were adequate to explain the variation among generations for crosses of SJC-1 X S5971 and SJC-1 X DPL70. Tolerance in these crosses appeared to be controlled by recessive factors. For the SJC-1 X 4-42 cross, an adequate fit to a digenic epistatic model was not possible, and none of the genetic parameters except the F₂ mean were significant. Heritabilities for tolerance to Verticillium wilt, determined from regressions of F₃ progeny on F₂ parents for the crosses of SJC-1 X S5971 and SJC-1 X DPL70, ranged from 0.12 to 0.28. Therefore, individual plant selection for improved tolerance is expected to be inefficient.Contribution from the Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA, to be included in a dissertation by the senior author in partial fulfillment of the Ph. D. degree     

Assessment of genes controlling Area under Disease Progress Curve (AUDPC) for stripe rust (P. Striiformis F. Sp. Tritici) in two wheat (Triticum Aestivum L.) crosses

Genetic effects on controlling stripe rust resistance were determined in two wheat crosses, Bakhiawar-92 × Frontana (cross 1) and Inqilab-91 × Fakhre Sarhad (cross 2) using Area under Disease Progress Curve (AUDPC) as a measure of stripe rust resistance. The resistant and susceptible genotypes for crosses were identified by initial assessment of 45 wheat accessions for stripe rust resistance. Mixed inheritance model was applied to the data analysis of six basic populations P ₁, F ₁, P ₂, B ₁, B ₂, and F ₂ in the crosses. The results indicated that AUDPC in cross 1 was controlled by two major genes with additive-dominance epistatic effect plus polygenes with additive-dominance epistatic effects (model E). Whereas in case of cross 2, it was under the control of two major genes with additive-dominance epistatic effect plus additive-dominant polygenes (model E-1). Additive effect was predominant then all other types of genetic effects suggesting the delay in selection for resistance till maximum positive genes are accumulated in the individuals of subsequent generations. Occurrence of transgressive segregants for susceptibility and resistance indicated the presence of resistance as well as some negative genes for resistance in the parents. The major gene heritability was higher than the polygene heritability in B ₁, B ₂ and F ₂ for the crosses. The major gene as well as the polygene heritability was ranging from 48.99 to 87.12% and 2.26 and 36.80% for the two crosses respectively. The highest phenotypic variations in AUDPC (2504.10 to 5833.14) for segregating progenies (BC ₁, BC ₂ and F ₂) represent that the character was highly influenced by the environment. The article is published in the original.     

Beneficial Effects of an Alternating High- Fat Dietary Regimen on Systemic Insulin Resistance,Hepatic and Renal Inflammation and Renal Function

Background

An Alternating high- cholesterol dietary regimen has proven to be beneficial when compared to daily high- cholesterol feeding. In the current study we explored whether the same strategy is applicable to a high- fat dietary regimen.

Objective

To investigate whether an alternating high- fat dietary regimen can effectively diminish insulin resistance, hepatic and renal inflammation and renal dysfunction as compared to a continuous high- fat diet.

Design

Four groups of male ApoE*3Leiden mice (n = 15) were exposed to different diet regimens for 20 weeks as follows: Group 1: low- fat diet (10 kcal% fat); Group 2: intermediate- fat diet (25 kcal% fat); Group 3: high- fat diet (45 kcal% fat) and Group 4: alternating- fat diet (10 kcal% fat for 4 days and 45 kcal% fat for 3 days in a week).

Results

Compared to high fat diet feeding, the alternating and intermediate- fat diet groups had reduced body weight gain and did not develop insulin resistance or albuminuria. In addition, in the alternating and intermediate- fat diet groups, parameters of tissue inflammation were markedly reduced compared to high fat diet fed mice.

Conclusion

Both alternating and intermediate- fat feeding were beneficial in terms of reducing body weight gain, insulin resistance, hepatic and renal inflammation and renal dysfunction. Thus beneficial effects of alternating feeding regimens on cardiometabolic risk factors are not only applicable for cholesterol containing diets but can be extended to diets high in fat content.