Reference "Transcript accumulation and utilization of alternate and non-consensus splice sites in rice granule-bound starch synthase are temperature- sensitive and controlled by a single-nucleotide polymorphism"

Reference ID

2348

Title

Transcript accumulation and utilization of alternate and non-consensus splice sites in rice granule-bound starch synthase are temperature- sensitive and controlled by a single-nucleotide polymorphism

Source

Plant molecular biology, 1999, vol. 40, pp. 719-727

Authors (2)

Larkin-P-D

Park-W-D

Abstract

Granule-bound starch synthase (GBSS), a product of the waxy gene in rice (Oryza
sativa L.), is necessary for the synthesis of amylose in the endosperm. In an
extended pedigree of 89 rice cultivars, we have previously shown that all
cultivars with more than 18% amylose had the sequence AGGTATA at the leader
intron 5' splice site, while all cultivars with a lower proportion of amylose
had the sequence AGTTATA. This single-nucleotide polymorphism reduces the
efficiency of GBSS pre- mRNA processing. It also results in alternate splicing
at multiple sites, some of which have non-consensus sequences. Here we
demonstrate that this same G-to-T polymorphism is also associated with
differential sensitivity to temperature during the period of grain development.
Cultivars with the sequence AGTTATA have a substantial increase in accumulation
of mature GBSS transcripts at 18 degrees C compared to 25 or 32 degrees C. The
selection of leader intron 5' splice sites is also affected by temperature in
these cultivars. A 5' splice site -93 upstream from that used in high-amylose
varieties predominates at 18 degrees C. At higher temperatures there is
increased utilization of a 5' splice site at -I and a non-consensus site at +1.
Potential implications of differential 5' splice site selection and associated
differences in 3' splice site selection on transcript stability and
translational efficiency are discussed.