| Goat is an important economic animal.There are differences in the meat quality of different breeds of goats.The study on its regulation mechanism is helpful to breed goats with good meat quality.Long-chain non-coding RNA(long non-coding RNA,lncRNA)is a kind of non-coding RNA molecules longer than 200 nt,which regulate gene expression at many levels,such as transcriptional level,posttranscriptional level,epigenetic regulation and so on.In recent years,it has been proved that lncRNA indirectly regulates skeletal muscle development by targeting genes,such as myoblast proliferation,differentiation and muscle fiber type conversion in many studies.In this study,the meat quality differences between Longlin goat and Nubian goat were compared and analyzed,and the difference lncRNAs in skeletal muscle between the two breeds of goats were mined by the next generation sequencing technologies,and the function of the screened new lncRNA was verified at the cellular level.The main test results are as follows:1.Meat quality test showed that the shear force of longissimus dorsi muscle of Nubian goat was significantly higher than that of Longlin goat(P<0.05),and the meat color score of Nubia goat was significantly lower than that of Longlin goat(P<0.05).However,there was no significant difference in p H value and electrical conductivity of longissimus dorsi muscle between the two goat breeds(P>0.05).The gene expression of type Ⅱb muscle fiber in the longissimus dorsi of Nubia goat was significantly higher than that of Longlin goat(P<0.05),the gene expression of type Ⅰ muscle fiber was significantly lower than that of Longlin goat(P<0.05),and the gene expression of type Ⅱa muscle fiber in Nubian goat was extremely significantly lower than that of Longlin goat(P<0.01).2.A total of 2796 lncRNA and 20587 mRNA were identified by high-throughput sequencing of longissimus dorsi muscle samples from Longlin and Nubian goats.There are 18 differentially expressed lncRNA and 460 differentially expressed mRNA between the two breeds.Functional analysis showed that the target genes of differentially expressed lncRNA and differentially expressed mRNA were mainly enriched in AMPK and PPAR signaling pathways,which are related to muscle growth and development and meat quality.3.The selected lncRNA-MSTRG.1847 related to meat quality traits was named as lncRMQ,and the target genes were predicted to be ADIPOQ and AQP7.The full-length sequence of lncRMQ was successfully amplified by RACE technology,its length of 646 bp.Tissue expression profile analysis showed that lncRMQ was only expressed in myocardium,longissimus dorsi muscle and leg muscle.Through software prediction and gene expression analysis,the mi RNA interacting with lncRMQ was initially screened as mi R-486.The target gene of mi R-486 is also ADIPOQ,mi R-486 is highly expressed in longissimus dorsi muscle,leg muscle and myocardium.It is speculated that lncRMQ-mi R-486-ADIPOQ plays a related role and participates in the regulation of goat skeletal muscle fiber type conversion.4.Using isolated goat primary skeletal muscle satellite cells as the carrier,after overexpressing lncRMQ,the expression level of mi R-486 in the cells was extremely significantly decreased,and the expression level of ADIPOQ was extremely significantly increased.After interfering with lncRMQ,the expression level of mi R-486 was extremely significantly increased,and the expression level of ADIPOQ was extremely significantly reduced.After overexpressing mi R-486,the expression level of ADIPOQ in the cells was extremely significantly reduced,and after interfering with mi R-486,the expression level of ADIPOQ gene was extremely significantly increased.After co-transfection of N1-lncRMQ and plv-mi R-486,the expression level of Adipoo Q in the cells was extremely significantly lower than that of the N1-lncRMQ group.In summary,this study found that the muscle quality of Longlin goat was better than that of Nubian goat,and there were differences in the expression level of mRNA and lncRNA in the longissimus dorsi between the two goat breeds.Candidate lncRMQ competitively combines mi R-486 to regulate the target gene ADIPOQ,thereby affecting the transformation of skeletal muscle fiber types and regulating muscle quality. |
