[Genetic relationship and population genetic diversity of Epimedium pubescens and its related species based on ISSR and non-glandular hair characteristic].

In this study, 128 individuals form 14 Epimedium pubescens populations and 1 E. stellulatum population were analyzed by ISSR marker. The data were calculated by POPGENE software and clustered by UPGMA method. Optical microscope was used to observe the main types of the non-glandular hairs and their characteristics in each population. It is found that the following conclusions: Non-glandular hairs can be divided into five morphological categories, long straight pubescent, curly pubescent, appressed curly pubescent, pseudo short appressed hairs and long appressed. Eight primers were screening and a total of 94 bands were detected in ISSR, among which 90 were polymorphic bands. Based on the results of ISSR cluster analysis, 15 populations were divided into 3 clades. E. stellulatum populations should be incorporated into the E. pubescens or as avariety under E. pubescens not be independent and as it has no separate phylogenetic branch for a cluster. The genetic relationship among the populations of E. pubescens was closely related with its geographical distribution and non-glandular hair features. But there were also some inconsistency, which provided a good hint for the further study on the interspecific relationship and natural speciation manner of Epimedium species. Population diversity analysis showed Nm=0.354 4, Nei's=0.585 2. It was showed that E. pubescens has high genetic diversity among populations, for which the main reason was probably the high inbreeding rate and the small range of seed dispersal.

Melatonin regulates the development and function of bovine Sertoli cells via its receptors MT1 and MT2.

Melatonin and its receptors are found in the testis of many species, where they mediate testicular functions. The present study aimed to investigate the expression of melatonin receptors (MT1 and MT2) in bovine Sertoli cells (SCs), using reverse transcription polymerase chain reaction (RT-PCR) and western blot. In addition, we assessed the mRNA levels of spermatogenesis-related genes (real-time PCR) and secretion of inhibin B after treatment with various concentrations (0, 80, 160, and 320 pg/mL) of melatonin at different time points (24, 48, or 72 h). We found that bovine SCs express MT1 and MT2 receptors, which were regulated by melatonin in time- and dose-dependent manners after treatment with melatonin. Exogenous melatonin up-regulated the expression of spermatogenesis-related genes, including Cyclin D1, Cyclin E, Pdgfa, Dhh, Occludin, and Claudin, and decreased the mRNA levels of P21 and Kit1 in a time or dose-dependent manner. Meanwhile, melatonin supplementation significantly affected Inhba, Inhbb and Inha mRNA expression. These findings were consistent with inhibin B levels detected in the culture medium. In conclusion, exogenous melatonin acts via its receptors and appears to play regulatory roles in the development and function of bovine SCs.

Three novel SNPs in the coding region of PPARγ gene and their associations with meat quality traits in cattle.

The peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear hormone receptor that regulates adipogenesis and many other biological processes. In the present study, we carried out PCR-SSCP and DNA sequencing analyses to examine SNPs in coding region of the PPARγ gene. A total of 660 individuals from five Chinese cattle breeds were genotyped. We identified three SNPs and their associations with meat quality traits were analyzed in 108 Qinchuan cattle. Two missense mutations and one synonymous mutation were found: 200 A>G (genotypes AA, AB and BB) resulting in D7G change, the silent substitution 42895 C>T (genotypes JJ and JI) and 72472 G>T (genotypes CC, DC and DD) producing Q448H change, respectively. The frequencies of PPARγ-A allele were 0.86, 0.83, 0.80, 0.72 and 0.87 for Qinchuan, Nanyang, Jiaxian, Luxi and Xianan populations, respectively. The frequencies of PPARγ-J allele varied from 0.87 to 0.96 in the five populations. In the 72472 G>T locus, the frequencies of PPARγ-C allele were higher than PPARγ-D allele in the five populations, and ranged from 0.58 to 0.82. Least squares analysis revealed that in 42895 C>T locus, there was a significant effect on tenderness in 18-20 months Qinchuan cattle (P<0.01), and in the 72472 G>T locus, animals with the genotype DC had lower mean values than these with genotype CC (P<0.01) for back fat thickness in 18-20 months, and animals with the genotype DD had lower mean values than these with genotypes CC and DC (P<0.01) for water holding capacity in 21-24 months (P<0.01). The SNPs we have identified may contribute to establishing a more efficient selection program for improving of genetic characteristics in indigenous Chinese cattle.