Bioinformatic Identification and Analysis of Cell Wall Extensins in ThreeArabidopsisSpecies

Abstract

Premise of research. Extensins (EXTs) are members of the cell wall hydroxyproline-rich glycoprotein superfamily and play important roles in plant growth, development, and defense. Bioinformatic analysis has identified EXTs for a number of plant species, including the model plant Arabidopsis thaliana, but none of these studies examined plants from the same genus.Methodology. Here we report on the bioinformatic identification and analysis of EXTs in Arabidopsis lyrata and Arabidopsis halleri, two of the closest relatives of A. thaliana, based on amino acid motif searches using the BIO OHIO 2.0 program. Phylogenetic trees for the various EXT subclasses were constructed using both maximum likelihood and maximum parsimony methods. Homologous proteins were revealed using the OrthoMCL program.Pivotal results. The total numbers and subclasses of EXTs were similar in all three species. In A. lyrata, 61 EXTs were identified, including 15 classical EXTs, 10 short EXTs, eight leucine-rich repeat EXTs (LRXs), 14 proli...