Reference "The amylose content in rice endosperm is related to the post- transcriptional regulation of the waxy gene"

Reference ID

4854

Title

The amylose content in rice endosperm is related to the post- transcriptional regulation of the waxy gene

Source

The Plant journal : for cell and molecular biology, 1995, vol. 7, pp. 613-622

Authors (8)

Wang-Z-Y	Zheng-F-Q
Shen-G-Z	Gao-J-P
Snustad-D-P	Li-M-G
Zhang-J-L	Hong-M-M

Abstract

The waxy (Wx) gene of rice encodes a granule-bound starch synthase (GBSS = waxy
protein) required for the synthesis of amylose in endosperm. An analysis of Wx
transcripts, Wx protein, and amylose content of 31 rice cultivars revealed that
endosperm amylose and Wx protein contents are correlated with the ability of the
cultivar to excise intron I from the leader sequence of the Wx transcript.
Cultivars with high endosperm amylose content (group I) contain high levels of
amylose, Wx protein, and the mature 2.3 kb Wx mRNA. Cultivars with intermediate
amylose content (group II) produce substantial amounts of a large 3.3 kb Wx pre-
mRNA, with intron I still present, in addition to the mature Wx mRNA, and
intermediate levels of Wx protein. Glutinous rice (group III cultivars) contains
no amylose, no Wx protein, and no mature Wx mRNA; only the incompletely spliced
3.3 kb Wx pre-mRNA is present in group III cultivars. Based on these results, it
is hypothesized that the amylose content of rice endosperm is regulated at the
level of Wx transcript processing, and, more specifically, at the stage of
intron I excision from the Wx pre-mRNA.