MADS-box genes are involved in floral organ identity and flowering.
Sheepgrass (Leymus chinensis) is an important perennial forage grass and
adapts well to several adverse environments. However, only a few studies on
the mechanism of flower development and the MADS-domain proteins are
available. The team of Junting Jia and Pincang Zhao from the Chinese Academy
of Sciences cloned 11 MADS-box genes from sheepgrass and studied their
The analysis revealed that most of these MADS-box genes are highly expressed
in floral organs. LcMADS1 and LcMADS3 showed higher expression in the stamen
than in the other tissues, while LcMADS7 showed high expression in the
stamen, glume, lemma and palea. Expressions of LcMADS2, LcMADS9, and
LcMADS11 were higher in vegetative organs than floral organs. Further
analysis showed that the expression of LcMADS1 and LcMADS2 were induced by
cold, while LcMADS9 was significantly upregulated by salinity.
These results suggest that several MADS-box genes, especially LcMADS1,
LcMADS3, and LcMADS7, play pivotal roles in sheepgrass sexual reproduction
and may also be involved in abiotic stress responses. These findings could
provide information for studies of MADS-box gene functions in rice, wheat,
and other cereals.