Analysis Of The Gene Sequence And Transcriptional Characteristics Of Acs-4 And Cpt-1 In Bursaphelenchus Xylophilus

In this study,we selected two fatty acid metabolism genes acs-4 and cpt-1 of Bursaphelenchus xylophilus,and analyzed their gene sequence structure characteristics.The transcriptional characteristics of the genes in the three developmental stages of B.xylophilus eggs,second instar larvae and adults were analyzed,and the transcriptional characteristics of the fatty acid degradation pathways of these two genes were specifically analyzed.Thereby,the developmental characteristics of B.xylophilus can be further explained to provide theoretical support for the study on fatty acid metabolism.1.The analysis of the gene sequence and protein structure of acs-4 and cpt-1 shows that in the front of the gene sequence,the plant parasitic nematode acs-4 is significantly different from the other two types of nematodes.The sequence similarity of acs-4 in animal parasitic nematode and free-living nematode is higher;cpt-1 shows high conservation among the three types of nematodes.2.Combining the evolutionary relationship with selective pressure analysis and protein functional differentiation analysis,the results shows that acs-4 is more positively selected and five positive selection sites are detected;cpt-1 is more stable and conservative,and prefers to the purify selection model.The function of ACS-4 in free-living nematode is similar to the the animal parasitic nematode,producing fewer functional differentiation sites;CPT-1 is very stable and no protein functional differentiation sites are detected.3.The transcriptional characteristics of acs-4 and cpt-1 during the development of B.xylophilus shows that acs-4 is significantly up-regulated in the three stages of B.xylophilus eggs,second instar larvae and adults.In addition to acs-4,B.xylophilus also has three other members of the ACS gene family,namely acs-3,acs-5 and acs-13,which exhibit different expression patterns during the development of B.xylophilus.And there is no significant correlation.cpt-1 does not show significant fluctuations in the expression of B.xylophilus,and the transcription level is very stable.Another member of the CPT gene family in B.xylophilus cpt-2 is significantly down-regulated during the egg stage to second instar larvaestage.It also shows a significant up-regulated from the second instar larvae stage to the adult stage.The downstream fatty acyl-CoA C-acyltransferase gene is down-regulated during egg stage to second instar larvae stage,but there is a significant up-regulation of the second instar larva stage to the adult stage.4.The transcriptional characteristics of some genes in the fatty acid degradation pathway of B.xylophilus were analyzed.The results shows that there are two groups of genes with similar expression patterns in the fatty acid degradation pathway of B.xylophilus.The first group contains four genes which are significantly up-regulated from egg stage to second instar larvae stage,and are down-regulated from the second instar larvae stage to adults stage:acyl-CoA synthetase gene acs-5,acyl-CoA dehydrogenase gene acdh-7,acyl-CoA oxidase gene and acetyl-CoA The acetyltransferase gene acat-1;the second group contains three genes which are significant down-regulated in the egg stage to the second instar larvae stage,and are significantly up-regulated from the second instar larva stage to adult stage: carnitine palmitoyltransferase II gene cpt-2,and two hydroxyacyl-CoA dehydrogenase genes.It is Extremely likely to have a mutually regulated relationship between genes of the same expression pattern.