Genome-Wide Analysis of the Pectin Methylesterase Gene Family in Potato

Pectin methylesterase (PME) is a type of protein encoded by a multi-gene family and participates in seed germination, fruit ripening and stress response. To further study the function of the PME gene family in potato, this paper screened and identified potato PME gene family by bioinformatics methods, and analysed the structure, physicochemical properties, conserved domains and evolutionary relationships of the gene sequences. The results showed that the identified 54 potato PME genes can be divided into Group I (only PME domain) and Group II (both PME domain and PMEI domain). The phylogenetic tree constructed by the maximum likelihood method indicated that potato PME genes consisted of five subfamilies. The protein sequences of potato PME genes were compared with clustalx2.1 software. Most of these sequences were identified to have five conserved structural regions including Gx Yx E (Region I), QAVAxR (Region II), QDTL (Region III), GxxDFIFG (Region IV) and YLGRxWx (Region V). Conserved motifs of potato PME amino acid sequences were analysed by MEME online software. Motif1 contains three of the five conserved structural regions and motif2 and motif8 each contain one, indicating that these sequences are more conservative. The structure of 54 potato PME gene sequences was analysed by the GSDS website. It was found that there were only two parts, exon or coding sequence (CDS) between untranslated regions (UTRs), without intron structures in these sequences, indicating that the structure is relatively simple. It will provide a reference for the study on the function of potato PME gene.