Phylogenetic analysis reveals dynamic evolution of the poly(A)-binding protein gene family in plants

摘要

BackgroundThe poly(A)-binding protein (PABP) binds the poly(A) tail of eukaryotic mRNAs and functions to maintain the integrity of the mRNA while promoting protein synthesis through its interaction with eukaryotic translation initiation factor (eIF) 4G and eIF4B. PABP is encoded by a single gene in yeast and marine algae but during plant evolution the PABP gene family expanded substantially, underwent sequence divergence into three subclasses, and acquired tissue-specificity in gene family member expression. Although such changes suggest functional specialization, the size of the family and its sequence divergence have complicated an understanding of which gene family members may be foundational and which may represent more recent expansions of the family to meet the specific needs of speciation. Here, we examine the evolution of the plant PABP gene family to provide insight into these aspects of the family that may yield clues into the function of individual family members.