GENOMIC SURVEY, CHARACTERIZATION AND EXPRESSION PROFILE ANALYSIS OF THE YELLOW STRIP LIKE GENE FAMILY IN RICE AND ARABIDOPSIS

Abstract

Genes in the YSL gene family encode for the metal transporter in plants. In this study, a comprehensive and comparative computational analysis of identified 18 and 8 YSL family genes in rice and Arabidopsis respectively have been carried out presenting a complete overview on gene structures, phylogeny, conserved motifs their distribution and relatedness, intron/ exon distribution and expression. The analysis in all indicated that YSL genes are relatively conserved gene family showing similarity on the basis of evolution and indicates their common ancestral origin. The multi-sequence alignment showed primary and secondary level of conservation at sequence level of YSLs in both rice Arabidopsis. YSL gene intron/ exon structure and domains were also found to be conserved during the evolution. Characterization of YSLs by sequence tag based methods of expression profiling viz ESTs and MPPS signatures showed a total of 833 ESTs and 382 MPSS tags co-localizing with the OsYSLs and 269 ESTs and 219 MPSS tags with AtYSLs. The expression pattern further analyzed digitally, by in silico microarrays in 22 tissues libraries, 8 stages of development and under different stimuli revealed assorted and preferential patterns of expression and provide an evidence for spatiotemporal regulation of these genes throughout plant development. OsYSL6 gene of rice showed very high as well as tissue specific expression under iron and phosphorous interaction by digital microarrays which were equally supported by ESTs and MPSS abundance. Similarly in Arabidopsis AtYSL1, 3 and 6 showed prominent expression in senescent leaves indicating their role in remobilization of metals.