Rice transcription factor OsMADS57 regulates plant height by modulating gibberellin catabolism

Abstract

Background The MADS-box transcription factors mainly function in floral organ organogenesis and identity specification. Few research on their roles in vegetative growth has been reported. Results Here we investigated the functions of OsMADS57 in plant vegetative growth in rice ( Oryza sativa ). Knockdown of OsMADS57 reduced the plant height, internode elongation and panicle exsertion in rice plants. Further study showed that the cell length was remarkably reduced in the uppermost internode in OsMADS57 knockdown plants at maturity. Moreover, OsMADS57 knockdown plants were more sensitive to gibberellic acid (GA 3 ), and contained less bioactive GA 3 than wild-type plants, which implied that OsMADS57 is involved in gibberellin (GA) pathway. Expectedly, the transcript levels of OsGA2ox3 , encoding GAs deactivated enzyme, were significantly enhanced in OsMADS57 knockdown plants. The level of EUI1 transcripts involved in GA deactivation was also increased in OsMADS57 knockdown plants. More importantly, dual-luciferase reporter assay and electrophoretic mobility shift assay showed that OsMADS57 directly regulates the transcription of OsGA2ox3 as well as EUI1 through binding to the CArG-box motifs in their promoter regions. In addition, OsMADS57 also modulated the expression of multiple genes involved in GA metabolism or GA signaling pathway, indicating the key and complex regulatory role of OsMADS57 in GA pathway in rice. Conclusions These results indicated that OsMADS57 acts as an important transcriptional regulator that regulates stem elongation and panicle exsertion in rice via GA-mediated regulatory pathway. Electronic supplementary material The online version of this article (10.1186/s12284-019-0298-6) contains supplementary material, which is available to authorized users.

Genome-Wide Analysis of the Shi-Related Sequence Family and Functional Identification of GmSRS18 Involving in Drought and Salt Stresses in Soybean

“…Transcription factors play vital roles in plant growth and development and many transcription factors have been identified to be involved in a series of progresses responding to abiotic and biotic stresses and signaling networks of plant hormones [37][38][39][40][41][42][43][44][45][46][47][48][49]. The annotation and structure analysis of many transcription factors in different plant species had been reported [50][51][52][53][54][55].…”

The Current Status of Research on Gibberellin Biosynthesis

“…Transcription factors that specify spatial and temporal expression patterns of GA-biosynthetic and inactivation genes have been identified, including KNOX, MADS-box and bHLH proteins. A recent example is the MADS-box protein OsMADS57, which directly promotes expression of the inactivation genes OsGA2ox3 and OsEUI1 to limit internode elongation and panicle exsertion in rice ( Chu et al. 2019 ).…”

Gene Expression Dynamics in Rice Peduncles at the Heading Stage

“…The effect of this can be observed with increased expression of GA deactivation genes after heading. For instance, CYP714B1 encoding gibberellin 13-oxidase which reduces gibberellin activity in rice as well as GA2ox4 and GA2ox6 , implicated in endogenous GA deactivation ( Chu et al, 2019 ), expressed at higher levels in peduncles after heading ( Lo et al, 2008 ; Magome et al, 2013 ). Overall, regulation of OsBRI1 by OsARF19 and its ( OsBRI1 ) role in deactivation of GA indicates interaction of auxin, brassinosteroids, and gibberellins in maintaining the hormonal homeostasis during peduncle elongation ( Zhang et al, 2015 ).…”

“…Till date, a handful of genes have been experimentally characterized to affect internode elongation through forward and/or reverse genetic strategies ( Rutger and Carnahan, 1981 ; Luo et al, 2006 ; Zhu et al, 2011 ; Duan et al, 2012 ; Gao et al, 2012 ; Magome et al, 2013 ; Ji et al, 2014 , 2019 ; Wang et al, 2017 ; Xie et al, 2018 ; Chu et al, 2019 ). However, lack of a comprehensive study to understand the overall gene expression dynamics during panicle elongation at the time heading is still limiting our understanding of panicle exsertion process in rice.…”