Reference "'Green revolution' genes encode mutant gibberellin response modulators"

Reference ID

3429

Title

'Green revolution' genes encode mutant gibberellin response modulators

Source

Nature, 1999, vol. 400, pp. 256-261

Authors (15)

Peng-J	Richards-D-E	Hartley-N-M	Murphy-G-P
Devos-K-M	Flintham-J-E	Beales-J	Fish-L-J
Worland-A-J	Pelica-F	Sudhakar-D	Christou-P
Snape-J-W	Gale-M-D	Harberd-N-P

Abstract

World wheat grain yields increased substantially in the 1960s and 1970s because
farmers rapidly adopted the new varieties and cultivation methods of the so-
called 'green revolution'. The new varieties are shorter, increase grain yield
at the expense of straw biomass, and are more resistant to damage by wind and
rain. These wheats are short because they respond abnormally to the plant growth
hormone gibberellin. This reduced response to gibberellin is conferred by mutant
dwarfing alleles at one of two Reduced height-1 (Rht-B1 and Rht- D1) loci. Here
we show that Rht-B1/Rht-D1 and maize dwarf-8 (d8) are orthologues of the
Arabidopsis Gibberellin Insensitive (GAI) gene. These genes encode proteins that
resemble nuclear transcription factors and contain an SH2-like domain,
indicating that phosphotyrosine may participate in gibberellin signalling. Six
different orthologous dwarfing mutant alleles encode proteins that are altered
in a conserved amino-terminal gibberellin signalling domain. Transgenic rice
plants containing a mutant GAI allele give reduced responses to gibberellin and
are dwarfed, indicating that mutant GAI orthologues could be used to increase
yield in a wide range of crop species.