title: Structure of the SHR-SCR heterodimer bound to the BIRD/IDD transcriptional factor JKD.
abstract: The plant-specific GAI, RGA and SCR (GRAS) family proteins play critical roles in plant development and signalling. Two GRAS proteins, SHORT-ROOT (SHR) and SCARECROW (SCR), cooperatively direct asymmetric cell division and the patterning of root cell types by transcriptional control in conjunction with BIRD/INDETERMINATE DOMAIN (IDD) transcription factors, although precise details of these specific interactions and actions remain unknown. Here, we present the crystal structures of the SHR-SCR binary and JACKDAW (JKD)/IDD10-SHR-SCR ternary complexes. Each GRAS domain comprises one α/β core subdomain with an α-helical cap that mediates heterodimerization by forming an intermolecular helix bundle. The α/β core subdomain of SHR forms the BIRD binding groove, which specifically recognizes the zinc fingers of JKD. We identified a conserved SHR-binding motif in 13 BIRD/IDD transcription factors. Our results establish a structural basis for GRAS-GRAS and GRAS-BIRD interactions and provide valuable clues towards our understanding of these regulators, which are involved in plant-specific signalling networks.
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Hirano
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Nakagawa
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Tomoe
authors.initials: T
authors.lastname: Suyama
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.|The Laboratory of Intercellular Communication, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Kohji
authors.initials: K
authors.lastname: Murase
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Maya
authors.initials: M
authors.lastname: Shirakawa
authors.affiliation: The Laboratory of Intercellular Communication, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Seiji
authors.initials: S
authors.lastname: Takayama
authors.affiliation: Department of Biology, Duke University, Durham, North Carolina 27708, USA.
authors.forename: Tai-Ping
authors.initials: TP
authors.lastname: Sun
authors.affiliation: Structural Biology Laboratory, Nara Institute of Science and Technology, 8916-5 Takayama, Ikoma, Nara 630-0192, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Hakoshima
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D014157:Transcription Factors / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D002352:Carrier Proteins; C523886:JACKDAW protein, Arabidopsis; C100978:SCR protein, Arabidopsis; C410510:SHORT ROOT protein, Arabidopsis; D014157:Transcription Factors