Allosteric receptor activation by the plant peptide hormone phytosulfokine

Jizong Wang; Hongju Li; Zhifu Han; Heqiao Zhang; Tong Wang; Guangzhong Lin; Junbiao Chang; Weicai Yang; Jijie Chai

doi:10.1038/nature14858

Allosteric receptor activation by the plant peptide hormone phytosulfokine

Nature. 2015 Sep 10;525(7568):265-8. doi: 10.1038/nature14858. Epub 2015 Aug 26.

Authors

Jizong Wang¹, Hongju Li², Zhifu Han¹, Heqiao Zhang¹, Tong Wang², Guangzhong Lin¹, Junbiao Chang³, Weicai Yang², Jijie Chai¹

Affiliations

¹ Ministry of Education Key Laboratory of Protein Science, Center for Structural Biology, School of Life Sciences, Tsinghua-Peking Joint Center for Life Sciences, Tsinghua University, Beijing 100084, China.
² State Key Laboratory of Molecular Developmental Biology, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing 100101, China.
³ School of Chemistry and Molecular Engineering, Zhengzhou University, Zhengzhou 450001, China.

PMID: 26308901
DOI: 10.1038/nature14858

Abstract

Phytosulfokine (PSK) is a disulfated pentapeptide that has a ubiquitous role in plant growth and development. PSK is perceived by its receptor PSKR, a leucine-rich repeat receptor kinase (LRR-RK). The mechanisms underlying the recognition of PSK, the activation of PSKR and the identity of the components downstream of the initial binding remain elusive. Here we report the crystal structures of the extracellular LRR domain of PSKR in free, PSK- and co-receptor-bound forms. The structures reveal that PSK interacts mainly with a β-strand from the island domain of PSKR, forming an anti-β-sheet. The two sulfate moieties of PSK interact directly with PSKR, sensitizing PSKR recognition of PSK. Supported by biochemical, structural and genetic evidence, PSK binding enhances PSKR heterodimerization with the somatic embryogenesis receptor-like kinases (SERKs). However, PSK is not directly involved in PSKR-SERK interaction but stabilizes PSKR island domain for recruitment of a SERK. Our data reveal the structural basis for PSKR recognition of PSK and allosteric activation of PSKR by PSK, opening up new avenues for the design of PSKR-specific small molecules.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Allosteric Regulation / drug effects
Arabidopsis / chemistry*
Arabidopsis Proteins / agonists*
Arabidopsis Proteins / chemistry*
Arabidopsis Proteins / genetics
Arabidopsis Proteins / metabolism
Crystallography, X-Ray
Models, Molecular
Mutation / genetics
Peptide Hormones / chemistry
Peptide Hormones / metabolism
Peptide Hormones / pharmacology
Plant Growth Regulators / chemistry*
Plant Growth Regulators / metabolism
Plant Growth Regulators / pharmacology*
Plant Proteins / chemistry
Plant Proteins / metabolism
Plant Proteins / pharmacology
Protein Binding
Protein Kinases / chemistry
Protein Kinases / metabolism
Protein Multimerization / drug effects
Protein Serine-Threonine Kinases / chemistry
Protein Serine-Threonine Kinases / metabolism
Protein Stability
Protein Structure, Secondary / drug effects
Protein Structure, Tertiary / drug effects
Receptors, Cell Surface / agonists*
Receptors, Cell Surface / chemistry*
Receptors, Cell Surface / genetics
Receptors, Cell Surface / metabolism
Substrate Specificity

Substances

Arabidopsis Proteins
PSK-alpha protein, plant
PSKR1 protein, Arabidopsis
Peptide Hormones
Plant Growth Regulators
Plant Proteins
Receptors, Cell Surface
Protein Kinases
SERK1 protein, Arabidopsis
Protein Serine-Threonine Kinases
somatic embryogenesis receptor-like kinase 2, Arabidopsis

Associated data

PDB/4Z5W
PDB/4Z61
PDB/4Z62
PDB/4Z63
PDB/4Z64