A STRUCTURE FUNCTION ANALYSIS OFsHSPsIN PLANTS

HERNÁN G. BONDINO , DÉBORA P. ARCE , ESTELA M. VALLE , TEN HAVE, ARJEN

Quilmes

Congreso; 1er Congreso Argentino de Bioinformática y Biología Computacional; 2010

<!-- /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:none; mso-layout-grid-align:none; text-autospace:none; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:"Times New Roman"; mso-ansi-language:EN-US; mso-fareast-language:#00FF;} @page Section1 {size:612.0pt 792.0pt; margin:2.0cm 2.0cm 2.0cm 2.0cm; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --> A structure function analysis of sHSPs in plants  Bondino, Hernán Gabriel*+; Valle, Estela Marta+; ten Have, Arjen*  *Intituto de Investigaciones Biológicas (IIB-CONICET), Mar del Plata.  +Instituto de Biología Molecular y Celular de Rosario (IBR-CONICET), Rosario.  hbondino@hotmail.com, valle@ibr.gov.ar, atenhave@mdp.edu.ar  Background : Small heat shock proteins (sHSPs) are associated with stress responses among which the heat shock response. They are believed to function as molecular chaperones in order to prevent proteins from being denatured in extreme conditions. Nonstress roles have also been suggested. sHSPs are ubiquitous in all three domains of life, and form a superfamily that consists of many small proteins that have an α-crystallin (AC) domain, that comprise about 100 amino acid residues. The AC domain is involved in preventing undesirable protein-protein interactions. Genome studies in lower plants indicate considerable structural and functional diversity. Recently, a number of higher plant genomes has become public which allows to elaborate on the previously performed studies in lower plants. Results : The genomes of Arabidopsis thaliana, rice, poplar, grape and tomato were mined in order to identify sHSPs. Strong differences in the number of sHSP encoding genes were found. In order to initiate a structure-function prediction analysis, we performed a multiple sequence alignment and phylogeny. Phylogeny showed the existence of a number of orthologous sHSP classes but also species specific paralogs. MEME identified a number of strongly conserved subsequences as well as a number of sHSPs classes. Results of co-evolution, evolutionary trace and DIVERGE analysis will be discussed in terms of both structure and function of the AC domain and sHSPs in plants.   Conclusions: sHSPs in higher plants form a large and various superfamily of proteins, that given the demonstrated variance in both sequence and tertiary structure might be involved in many aspects of plants´ survival. More studies will be required in order to obtain insight in how sHSP interact with other proteins.