Identification Of Gene Family And Molecular Evolution Research In Populus Trichocarpa

As a model tree species of woody plants,poplar has important economic value and ecological value.The gene duplication mechanism leads to a large number of duplicate genes in plant.Many duplicated genes have an important contribution to maintaining the normal morphology and physiological of plants.By studying the duplicate gene features,it can help researchers find genes that respond to abiotic stress from a large number of genes.In this study,first,34558 duplicated genes were identified from the Populus trichocarpa genome,followed by analysis of the evolution rate,gene features,and expression patterns under abiotic stress under different selection modes.A Populus trichocarpa gene family database was constructed,as well as an evolutionary analysis of the Populus trichocarpa VQ gene family and its response to salt stress.The following main results were obtained:1 Obtained 34092 negative selection genes and 1544 positive selection genes.2 Negative selection genes had longer gene sequences,more exons,higher GC content,higher expression levels,wider expression,more GO terms,a higher proportion of differentially expressed genes and differential intron retention genes.3 The expression levels of negative selection genes showed significant negative correlations with K_aand K_s,while the expression levels of positive selection genes showed significant positive correlations with K_a,K_sand K_a/K_s.4 Constructed the Populus trichocarpa gene family database(GFDP)(http://gfdp.ahau-edu.cn/).The database collected 145 Populus trichocarpa gene families and 6551 genes,and carried out annotation and visualization of structure,evolution and function.5 The Populus trichocarpa VQ gene had 51 members,including 64 duplicated gene pairs,with the highest percentage of whole genome duplication,accounting for59.38%.6 Duplicated gene pairs with differentially expressed genes respond to asymmetric function under salt stress.7 Subcellular localization showed that the PtVQ1 was located in the nucleus and cell membrane,and the PtVQ13 was located in the nucleus.