Expression Analysis Of Genes Within Wnt/β-catenin Signaling Pathway In Goat Cashmere Cyclical Regeneration And Pigmentation

Aim of this thesis was to explore relative expression of genes mRNA withinWnt/β-catenin signalling pathway in goat cashmere cyclical regeneration andpigmentation,and lay foundation for elucidating the molecular mechanisms that Wnt/β-cateninsignalling pathway regulate cashmere cyclical regeneration and pigmentation finally.Wefocused on a candidate gene Wnt3wh ich as a member of Wnt gene family and controllinghair shaft structure and length by modulating the process of hair shaft progenitor cellsdifferentiated to progeny cells that make up hair shaft. Methods such as genecloning,bioinformatic analysis and prokaryotic expression were employed in firstexperiment.Quantitative real-time PCR was adopted in second experiment to detect relativemRNA expresssion of genes such as Wnt3,β-catenin,Lef1and other genes withinWnt/β-catenin signalling pathways in white cashmere goat skin tissue at different stage ofgrowth. mRNA relative expression of genes mentioned above in skin tissue between whiteand black goat in the mddile of anagen was also perfomed in the sameexperiment.Otherwise,genes including MITF,ASIP and TYR gene family were chosen to testrelative expression of their mRNA in skin tissue between white and black goat in the mddileof anagen by quantitative real-time PCR.Results indicated as follows:(1) Full length of Wnt3gene coding sequence is1068bp and355amino acids wereencoded;different species shared high similarity,which above ninety percentage;fomula ofcoding peptide was C1733H2688N508O510S29;molecular weight of coding peptide was40KDa;isoelectric point of coding peptide was7.75;instability index of coding peptide was46.47,showing that this peptide as unstable protein; coefficient of fat for coding protein was69.24,demonstrating it as a hydrophobic protein;four palmitoylation sites were predicted byspecific software,this sites started at215,314,315and337, respectively;none O-glycosylationsite and a unique N-glycosylation site exsited according the prediction results;coding proteinwas exocrine,and splicing site appeared at locus21;Wnt-1domain occurred at proteinsequcence;targeted protein showed up in sediment induced by IPTG. (2) relative expression of genes mRNA upgraded at onset of anagen，peaked at middle ofanagen and down-regulated step by step in later anagen until telogen，which was the lowest inwhite goat skin tissue among different growth stages;relative expression of genes mRNAshowed no significant difference in skin tissues between black and white goat in the middle ofanagen（P﹥0.05）(3) MITF and genes within TYR gene family mRNA expression was significantly higher inblack goat than white,whereas ASIP gene mRNA expression was dramatically higher in whitegoat than black.All results showed that wnt3gene and correspondent protein shared common featureswith genes and protein of Wnt family; Wnt/β-catenin pathway is related to cashmere cyclicalregeneration and promoted rapid growth of cashmere in the middle of anagen.Cashmerepi-gmentation was not related with Wnt/β-catenin pathway; genes such as MITF,ASIP andTYR gene family participated in the pigmentation of cashmere,but might not be regulated byWnt/β-catenin pathway.