| An11.7-kb deletion region, which located in1q23triggers intersexuality and polledness ingoat, now called Polled Intersex Syndrome (PIS). The PIS-deleted11.7-kb DNA fragmentencompasses no coding regions but exerts transcriptional regulatory effects on at least2genes and long transcripts located nearby. The2genes are PISRT1(PIS regulatedtranscript number1), FOXL2(forkhead bos L2). Between the two genes, PISRT1could beclassified as long non-coding RNA (ln RNA), and was first affirmed as an anti-testis gene.FOXL2appears to be a classic type, encoding a transcription factor, carrying the ovariandifferentiating function.PIS-deleted is not the only reason that caused polled intersexual dairy goats. So wefirst identified the sexuality, and attempted to investigate the genetic sex basis of intersexdairy goats. In order to examine the variations of PISRT1and FOXL2in the hornlessintersex goats, polymorphism was analyzed. Using the bioinformatatics software, wepredicted the promoter region and analyzed the activity area of FOXL2promoter.A total number of34intersex dairy goats were identified, and the SRY gene was notdetected in PIS goats, indicating that the PIS goat was absent with SRY gene and theirgenetic sex basis was female.With the help of direct sequencing and alignment of PISRT1gene for33intersex and28normal samples, two SNPs were detected (g.7032G>A and g.7049G>C). In the intersexdairy goats, the CC genotype frequency (0.667) was obvious higher than CG genotypefrequency (0.333). Chi-squares test between normal and intersex individual showed thedifference was extremely significant (P<0.01); The CG genotype frequency (0.857) in thehorned goats was higher than CC genotype frequency (0.143). Chi-squares test wasextremely significant (P<0.01) between the horned and polled individuals.The result of the promoter prediction with the bioinformatics software was not theonly. We found a TATA–box at-1558. Meanwhile, an important transcription factorNFI/CTF, which was closely connected with RNA polymerase. At the same location,TFIID was predicted. It is a transcription factor that combines with upstream, such asCAAT-box and GC–box. So, we inferred that the promoter of gene was according to theTATA–box, and-1700~-50was the candidate promoter segment.To analyze the promoter feature of FOXL2gene, we constructed the luciferase report gene plasmid. The result of promoter activity analysis showed that the main positiveregulation fragment of FOXL2promoter might-456~-192, the fragment of-934~-456might contain inhibiting elements of transcription, and the core promoter region was-32~+324. |
