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Bama Xiang pig (BM) and Tibetan mini-pig (TM) are used as experimental animals in China; however, the dwarf molecular mechanisms of these Chinese local pig breeds are unknown. IGFBP-3 affects animal growth, carcass and meat quality. The aim of this study was to identify the polymorphisms in the promoter of theIGFBP-3and analyse their effect on theIGFBP-3mRNA expression level in liver and muscle tissues. High-density single-nucleotide polymorphisms (SNPs) (31) and InDels (5) were detected in the promoter of theIGFBP-3in the BM, TM and Junmu No. 1 White (JM, control) pig breeds from 114 individuals by re-sequencing. A perfect Linkage disequilibrium consisted of 13 SNPs was observed in the promoter region and 2 main haplotypes were identified, of which theh1genotype (GCA-ATGTACATAT) was more prevalent in JM breed than in TM or BM breeds (P < .0001),h2(ATGTGCACG--CGC) was the dominant haplotype in TM and BM breeds (P < .0001). Expression analysis showed that haplotype of the promoter region is highly associated with theIGFBP-3mRNA expression level in liver and muscle tissues of pigs. TheIGFBP-3mRNA expression level was determined higher in the liver and muscle tissues of pigs withh2genotype as compared to that in pigs withh1genotype (P < .05). The results suggest that the SNPs and haplotypes in the promoter of theIGFBP-3gene may serve as useful molecular markers for the body growth traits and the breeding in swine. [ABSTRACT FROM AUTHOR]

Insulin-like growth factor binding protein 6 (IGFBP6) is a key factor in regulating the effects of insulin-like growth factor 2 (IGF2) on the animal growth and development, but the mechanism is far from known. In this study, the 5'-terminal sequence of theIGFBP6gene (from −920 to −1 bp) which may regulate gene expression was sequenced in the Bama mini-pigs, the Tibetan mini-pigs, the Landrace pigs, the Large White pigs and the Northeast wild boars to screen for the single nucleotide polymorphisms (SNPs) and analyze the relations with the body size traits of swine through a chi-square test analysis. The genotype frequencies of the SNPs in the 5'-terminal sequence have shown that c.-726C > T, c.-722T > C, c.-535C > A, c.-488T > C, c.-403A > G, and c.-378T > C may be related to the dwarf traits of the Bama mini-pig and the Tibetan mini-pigs (P < .05). A haplotype analysis of the 5'-terminal sequence of theIGFBP6gene in the Landrace pigs, the Large White pigs and the Northeast wild boars found the two SNPs at −403 nt and −378 nt were in linkage and formed three kinds of haplotypes; AT was the dominant haplotype and the haplotype block was not formed in the Bama mini-pigs and Tibetan mini-pigs. Above all, the SNPs and haplotypes of the 5'-terminal sequence of theIGFBP6gene may be involved in the regulation of swine body size. [ABSTRACT FROM AUTHOR]

The Nramp1/Slc11a1 locus encodes a proton-coupled divalent cation transporter, expressed in late endosomes/lysosomes of macrophages, that constitutes a component of the innate immune response to combat intracellular pathogens and it was shown to play an important role in regulating inherent immunity. The previously identified Z-DNA forming polymorphic repeat(GT)n in the promoter region of the human Nramp1 gene does act as a functional polymorphism influencing gene expression. Research has shown that INF-γ, TNF-α, IL-1β and bacteria LPS increase the level of Nramp1 expression. However, the molecular mechanism for Nramp1 gene regulation is unclear. In this research, bovine Nramp1 5′-flanking region (−1748~+769) was cloned and analyzed by bioinformatics. Then to find the core promoter and the cis-acting elements, deletion analysis of promoter was performed using a set of luciferase reporter gene constructs containing successive deletions of the bovine Nramp1 5′-flanking regions. Promoter activity analysis by the dual luciferase reporter assay system showed that the core promoter of Nramp1 was located at +58~−89 bp. Some positive regulatory elements are located at −89~−205 bp and −278~−1495 bp. And the repressor elements were in region −205~−278 bp, intron1 and −1495~−1748 bp. LPS-responsive regions were located at −1495~−1748 bp and −278~−205 bp. The present study provides an initial effort to explore the molecular mechanism of transcriptional activation of the bovine Nramp1 gene and should facilitate further studies to decode the complex regulatory process and for molecular breeding for disease resistance in bovines. [ABSTRACT FROM PUBLISHER]

The decrease in sperm quality under heat stress causes a great loss in animal husbandry production. In order to reveal the mechanism underlying the sperm quality decrease caused by heat stress, we first established a mild heat-treated mouse model. Then, the sperm quality was identified. Further, the testicular proteome profile was mapped and compared with the control using 2D electrophoresis and mass spectrometry. Finally, the differential expressed proteins involved in the heat stress response were identified by real-time PCR and Western blotting. The results showed that heat stress caused a significant reduction in mouse sperm quality (P<0.05). Further, 52 protein spots on the 2D gel were found to differ between the heat-shocked tissues and the control. Of these spots, some repair proteins which might provide some explanation for the influence on sperm quality were found. We then focused on Bag-1, Hsp40, Hsp60 and Hsp70, which were found to be differently expressed after heat shock (P<0.05). Further analysis in this heat-shocked model suggests numerous potential mechanisms for heat shock-induced spermatogenic disorders. [ABSTRACT FROM AUTHOR]