Physcomitrella Moss (physcomitrella Patens) Plant Microrna Binding Target Prediction

Bryophytes include three groups:liverworts(Marchantiophyta),hornworts (Anthocerotophyta) and mosses(Bryophyta).Physcomitrella patens belongs to Funariaceae, Physcomitrella.P.patens has a high frequency of homologous recombination.It possesses a unique position in the evolution from alga to higher plant.Besides,P.patens has an extreme ability to tolerate salt and drought.Therefore,P.patens has been becoming an important model organism.Till March 2007,with the completion of chloroplast genome,mitochondrion genome and genome draft sequencing,P.patens enters the genomic age.miRNAs are a class of non-coding endogenous small RNA with a length of 21～24 nucleotides.They have been discovered both in animals and plants,and play a wide range of biological functions,miRNAs are now believed to share the same important roles in gene expression regulation as transcription factors.Since the sequences of most miRNAs are highly conserved among close related species,and miRNAs display perfect or almost perfect sequence complement to their target mRNA sequences,it is feasible to predict the plant miRNA targets using bioinformatic approaches.In the present work,857 plant miRNAs were used to search 27546 P.patens mRNAs with PatScan for complementary hits.162 miRNA families had potential targets in P.patens.The number of targets and the position in miRNA co-regulation network both indicated that miR482 and miR1168 may play crucial roles in P.patens.52 Chlamydomonas reinhardtii specific miRNAs and many flowering plant miRNAs simultaneously having targets in P.patens suggested the moss occupied a unique phylogenetic position from algae to seeding plants.Next,we will predict P.patens miRNAs through its whole genome sequence and corresponding miRNA targets.This work lays a foundation for the further study of P.patens miRNAs.