Poster: Temperature Responses

Abs # 189: Expression profile of nine members of rice class I sHSP gene family

Presenter:	Lin, Chu-Yung , chuyung@ccms.ntu.edu.tw
Authors	Lin,  Chu-Yung  (A)   Jinn, Tsung-Luo  (A)   Feng, Shih-Pin  (A)   Guan, Jiahn-Chou  (A)
Affiliations:	(A): Department of Botany, National Taiwan University

In rice (Oryza sativa Tainung No.67), the cytosolic class I sHSP family consists of 9 members. They are (Oshsp16.9A, (Oshsp16.9B, (Oshsp16.9C, (Oshsp16.9D and (Oshsp17.9B clustered on chromosome 1 and (Oshsp17.3, (Oshsp17.7, (Oshsp17.9A and (Oshsp18.0 clustered on chromosome 3, respectively. These genes share high homology in the coding regions (>80%) and low in the 3¡¦-UTRs (<40%). Comparing with the native HS complex, we have identified the corresponding protein spots of the nine gene products on the 2-D gel using the coupled in vitro transcription/translation and recombinant protein expression systems. The defined feature of HSP genes i.e. heat shock element (HSE) was also recognized in the 5¡¦-upstream regions of these genes. It was interesting to note that the ~1.6-kb 5¡¦-upstream regions of (Oshsp16.9A and (Oshsp16.9B are identical. Furthermore, (Oshsp17.3 and (Oshsp18.0 were arranged apart with 360 bp in length by head-to-head orientation on the opposite DNA duplex strand. To establish detailed expression data of this gene family in response to heat stress and also to other agents, a comprehensive RT-PCR analysis was conducted. Our preliminary results indicated that the induction and accumulation of the rice class I sHSP mRNA levels were not identical in the members. The possible mechanisms operative for the differential expression will be discussed. This work was supported by the National Science Council, Taiwan (grants Nos. NSC90-2311-B-002-034 and NSC90-2311-B-002-056 to C. Y. Lin.)