Reference "Genome-wide analysis, evolutionary expansion, and expression of early auxin-responsive SAUR gene family in rice (Oryza sativa)"

Reference ID

11151

Title

Genome-wide analysis, evolutionary expansion, and expression of early auxin-responsive SAUR gene family in rice (Oryza sativa)

Source

Genomics, 2006, vol. , pp. -

Authors (3)

Jain-M	Tyagi-A-K
Khurana-J-P

Abstract

Small auxin-up RNAs (SAURs) are the early auxin-responsive genes represented by
a large multigene family in plants. Here, we report the identification of 58
OsSAUR gene family members from rice (Oryza sativa japonica cv Nipponbare), the
model monocot plant, by a reiterative database search and manual reannotation; 2
of these are pseudogenes. The coding sequences of OsSAURs do not possess any
intron. Most of the predicted OsSAUR protein sequences harbor a putative nuclear
localization signal at their N-terminus. Localized gene duplications appear to
be the primary genetic event responsible for SAUR gene family expansion in rice.
Interestingly, the duplication of OsSAURs was found to be associated with the
chromosomal block duplication as well. The phylogenetic analysis revealed that
the SAUR gene family expanded in rice and Arabidopsis due to species-specific
expansion of the family in monocots and dicots. The auxin-responsive elements
and downstream element are conserved in the upstream and downstream sequences,
respectively, of OsSAURs. In addition to the 21 OsSAURs with full-length cDNA
sequences and 20 with expressed sequence tags, gene expression analyses of at
least 7 OsSAURs by RT-qPCR indicated that the majority of identified OsSAURs
most likely are expressed in rice. The transcript abundance of the OsSAURs
examined increased within a few minutes of exogenous auxin application with
varying kinetics. The present study provides basic genomic information for the
rice SAUR gene family and will pave the way for deciphering the precise role of
SAURs in plant growth and development.