Reference "DTH8 suppresses flowering in rice, influencing plant height and yield potential simultaneously"

Reference ID

54920

Title

DTH8 suppresses flowering in rice, influencing plant height and yield potential simultaneously

Source

Plant Physiol, 2010, vol. 153, pp. 1747-1758

Authors (10)

Wei-X	Xu-J
Guo-H	Jiang-L
Chen-S	Yu-C
Zhou-Z	Hu-P
Zhai-H	Wan-J

Abstract

The three most important agronomic traits of rice (Oryza sativa), yield, plant
height, and flowering time, are controlled by many quantitative trait loci
(QTLs). In this study, a newly identified QTL, DTH8 (QTL for days to heading on
chromosome 8), was found to regulate these three traits in rice. Map-based
cloning reveals that DTH8 encodes a putative HAP3 subunit of the CCAAT-box-
binding transcription factor and the complementary experiment increased
significantly days to heading, plant height, and number of grains per panicle in
CSSL61 (a chromosome segment substitution line that carries the nonfunctional
DTH8 allele) with the Asominori functional DTH8 allele under long-day
conditions. DTH8 is expressed in most tissues and its protein is localized to
the nucleus exclusively. The quantitative real-time PCR assay revealed that DTH8
could down-regulate the transcriptions of Ehd1 (for Early heading date1) and
Hd3a (for Heading date3a; a rice ortholog of FLOWERING LOCUS T) under long-day
conditions. Ehd1 and Hd3a can also be down-regulated by the photoperiodic
flowering genes Ghd7 and Hd1 (a rice ortholog of CONSTANS). Meanwhile, the
transcription of DTH8 has been proved to be independent of Ghd7 and Hd1, and the
natural mutation of this gene caused weak photoperiod sensitivity and shorter
plant height. Taken together, these data indicate that DTH8 probably plays an
important role in the signal network of photoperiodic flowering as a novel
suppressor as well as in the regulation of plant height and yield potential.