JXB Advance Access originally published online on November 30, 2006
Journal of Experimental Botany 2007 58(3):483-495; doi:10.1093/jxb/erl217
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
RESEARCH PAPER |
The role of the sucrose transporter, OsSUT1, in germination and early seedling growth and development of rice plants
1CSIRO Plant Industry, Canberra, ACT 2601, Australia
2Department of Rice Research, National Agricultural Research Center, Joetsu, Niigata 943-0193, Japan
3National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan
To whom correspondence should be addressed. E-mail: robert.furbank{at}csiro.au
Using expression analysis, the role of the sucrose transporter OsSUT1 during germination and early growth of rice seedlings has been examined in detail, over a time-course ranging from 1 d to 7 d post-imbibition. Unlike the wheat orthologue, TaSUT1, which is thought to be directly involved in sugar transfer across the scutellar epithelium, OsSUT1 is not expressed in the scutellar epithelial cell layer of germinating rice and is, therefore, not involved in transport of sugars across the symplastic discontinuity between the endosperm and the embryo. OsSUT1 expression was also absent from the aleurone cells, indicating it is not involved in the transport of sucrose in this cell layer during germination. However, by 3 d post-imbibition, OsSUT1 was present in the companion cells and sieve elements of the scutellar vascular bundle, where it may play a role in phloem loading of sucrose for transport to the developing shoot and roots. This sucrose is most likely sourced from hexoses imported from the endosperm. In addition, sucrose may be remobilized from starch granules which are present at a high density in the scutellar ground tissues surrounding the vasculature and at the base of the shoot. OsSUT1 was also present in the coleoptile and the first and second leaf blades, where it was localized to the phloem along the entire length of these tissues, and was also present within the phloem of the primary roots. OsSUT1 may be involved in retrieval of sugars from the apoplasm in these tissues.
Key words: Germination, OsSUT1, rice, sucrose transport, sugar uptake
* Present address: Laboratory of Crop Science Graduate School of Agriculture and Life Science, University of Tokyo, 1-1-1 Yayoi, Bunko, Tokyo 113-8657, Japan.
Received 5 July 2006; Revised 27 September 2006 Accepted 28 September 2006
CiteULike 
Connotea 
Del.icio.us What's this?
This article has been cited by other articles:
|
|
 |
|
  H. Fallahi, G. N. Scofield, M. R. Badger, W. S. Chow, R. T. Furbank, and Y.-L. Ruan Localization of sucrose synthase in developing seed and siliques of Arabidopsis thaliana reveals diverse roles for SUS during development J. Exp. Bot., July 16, 2008; (2008) ern180v1. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
G. N. Scofield, T. Hirose, N. Aoki, and R. T. Furbank Involvement of the sucrose transporter, OsSUT1, in the long-distance pathway for assimilate transport in rice J. Exp. Bot., September 1, 2007; 58(12): 3155 - 3169. [Abstract] [Full Text] [PDF]
|
|