SHALLOT-LIKE1 is a KANADI transcription factor that modulates rice leaf rolling by regulating leaf abaxial cell development.
As an important agronomic trait, rice (Oryza sativa L.) leaf rolling has attracted much attention from plant biologists and breeders. Moderate leaf rolling increases the photosynthesis of cultivars and hence raises grain yield. However, the relevant molecular mechanism remains unclear. Here, we show the isolation and functional characterization of SHALLOT-LIKE1 (SLL1), a key gene controlling rice leaf rolling. sll1 mutant plants have extremely incurved leaves due to the defective development of sclerenchymatous cells on the abaxial side. Defective development can be functionally rescued by expression of SLL1. SLL1 is transcribed in various tissues and accumulates in the abaxial epidermis throughout leaf development. SLL1 encodes a SHAQKYF class MYB family transcription factor belonging to the KANADI family. SLL1 deficiency leads to defective programmed cell death of abaxial mesophyll cells and suppresses the development of abaxial features. By contrast, enhanced SLL1 expression stimulates phloem development on the abaxial side and suppresses bulliform cell and sclerenchyma development on the adaxial side. Additionally, SLL1 deficiency results in increased chlorophyll and photosynthesis. Our findings identify the role of SLL1 in the modulation of leaf abaxial cell development and in sustaining abaxial characteristics during leaf development. These results should facilitate attempts to use molecular breeding to increase the photosynthetic capacity of rice, as well as other crops, by modulating leaf development and rolling.
Zhang
Guang-Heng
GH
State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou 310006, Zhejiang, China.
Xu
Qian
Q
Zhu
Xu-Dong
XD
Qian
Qian
Q
Xue
Hong-Wei
HW
D000595:Amino Acid Sequence; D029681:Arabidopsis Proteins / Q000145:classification / Q000235:genetics / Q000378:metabolism*; D002734:Chlorophyll / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D017930:Genes, Reporter; D017403:In Situ Hybridization; D008969:Molecular Sequence Data; D005810:Multigene Family; D012275:Oryza / Q000033:anatomy & histology / Q000235:genetics; D010788:Photosynthesis / Q000502:physiology; D018515:Plant Leaves / Q000166:cytology* / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D016415:Sequence Alignment; D014157:Transcription Factors / Q000145:classification / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; C430846:KANADI protein, Arabidopsis; D010940:Plant Proteins; D014157:Transcription Factors; D002734:Chlorophyll