Genome-Wide Analysis of HAESA/HAESA-Like Kinase Family in Rice

In leucine-rich repeat (LRR) receptor-like kinase XI subfamily, Arabidopsis HAESA (AtHAE) and two closely related HAESA-LIKE (AtHSL1 and AtHSL2) constitute a small branch. Several reports have described the function and the involved signaling pathway that AtHAE and AtHSLs are involved in. However, the family members and functions of HAE and HSL in rice have not been reported. Here, we performed a genome-wide analysis of the HAE/HSL kinase family in rice. A total of 17 OsHSLs were identified in the genome. Of these, only Os11g11890 was annotated as HSL2;all the other members were annotated as HSL1. Phylogenetic analysis revealed that OsHSLs diverged into three groups, with three Arabidopsis members constituting a subgroup of group I. Domain analysis revealed that all the homologues had 9-19 LRR repeats and a typical kinase domain at the C-terminus, except that four members lost or evolved their kinase domains. Expression analysis revealed that OsHSLs were co-expressed with genes involved in biotic and abiotic stresses. Microarray data revealed that most OsHSLs were highly expressed in the vegetative tissues and only two members were highly expressed in the reproductive tissues. Most OsHSLs changed their expression profiles when subjected to drought, and salt stress treatments. Our results provide an overview of OsHSL gene family in rice, and suggest that OsHSLs possibly function under biotic and abiotic stresses, thus would help for elucidating the function of OsHSLs gene family in vivo.