Reference "Isolation of a cDNA for tryptophan synthase beta from rice and studies of its expression in a 5-methyltryptophan-resistant mutant of rice"

Reference ID

2109

Title

Isolation of a cDNA for tryptophan synthase beta from rice and studies of its expression in a 5-methyltryptophan-resistant mutant of rice

Source

Plant molecular biology, 1998, vol. 38, pp. 875-878

Authors (4)

Kisaka-H	Kisaka-M
Lee-H-Y	Kameya-T

Abstract

A cDNA clone encoding rice tryptophan synthase beta (TSB) was isolated and its
transcript level was examined in TR-No. 73, a derivative of a previously
isolated rice mutant (TR-1) that is resistant to 5- methyltryptophan. The cDNA
sequence of the rice gene for TSB was very similar to that of genes for TSB from
other plants. Northern blotting analysis revealed that the steady-state level of
TSB mRNA in the 5MT- resistant mutant TR-No. 73 was 1.3 times higher than the
level of TSB mRNA in control rice plants under standard conditions. The level of
TSB mRNA in control rice plants decreased after treatment of plants with 5MT.
Similarly, the level of TSB mRNA in TR-No. 73 initially decreased, although less
so than in control rice. However, after 12 h of treatment with 5MT, the level of
the transcript in TR-No. 73 returned to the level under standard conditions. The
activity of tryptophan synthase (TS) in seedlings of TR-No. 73 was about 2.3
times higher than that in seedlings of control rice under standard conditions.