Vitis vinifera ( grape ) is one of the most economically significant fruit crops in the world. The availability of the recently released grape genome sequence offers the opportunity to identify and analyze some important gene families in this species. Subtilases are a group of subtilisin-like serine proteases that are involved in many biological processes in plants. However, no comprehensive study incorporating phylogeny, chromosomal location and gene duplication, gene organization, functional divergence, selective pressure and expression profiling has been reported so far for the grape.   

Recently, the research group led by Prof. HU Xiangyang and Prof. HUANG Jinling from Kunming Institute of Botany ,cooperating with Dr. CAO Jun from Jiangsu University, performed a comprehensive analysis of the subtilase gene family in V. vinifera Eighty subtilase genes were identified. Phylogenetic analyses indicated that these subtilase genes comprised eight groups. The gene organization is considerably conserved among the groups. Distribution of the subtilase genes was non-random across the chromosomes. A high proportion of these genes are preferentially clustered, indicating that tandem duplications may have contributed significantly to the expansion of the subtilase gene family. Analyses of divergence and adaptive evolution show that while purifying selection may have been the main force driving the evolution of the subtilases, some of the critical sites responsible for the divergence may have been under positive selection. Further analyses of real-time PCR data suggested that many subtilase genes might be important in the stress response and functional development of plants. These results show that tandem duplications as well as purifying and positive selections have contributed to the functional divergence of subtilase genes in V. vinifera. The data may contribute to a better understanding of the grape subtilase gene family. 

This work was supported by the Young Academic and Technical Leader Raising Foundation of Yunnan Province ( No.2012HB041 ) and the Natural Science Foundation of China ( NSFC ) Overseas Hong Kong and Macao collaborative grant ( 31328003 ). This manuscript entitled “Genome-wide and molecular evolution analysis of the subtilase gene family in Vitis vinifera” was published on BMC genomics. The paper link: http://www.biomedcentral.com/content/pdf/1471-2164-15-1116.pdf 

Phylogenetic relationships and gene structures of grape subtilase genes. ( Image by KIB )