Phytosulfokine-α(PSK-α),a sulfated pentapeptide with the sequence YIYTQ,is encoded by a small precursor gene family in Arabidopsis.PSK-αregulates multiple growth and developmental processes as a novel peptide hormo...Phytosulfokine-α(PSK-α),a sulfated pentapeptide with the sequence YIYTQ,is encoded by a small precursor gene family in Arabidopsis.PSK-αregulates multiple growth and developmental processes as a novel peptide hormone.Despite its importance,functions of PSK-αin M.truncatula growth remains unknown.In this study,we identified five genes to encode PSK-αprecursors in M.truncatula.All of these precursors possess conserved PSK-αsignature motif.Expression pattern analysis of these MtPSK genes revealed that each gene was expressed in a tissue-specific or ubiquitous pattern and three of them were remarkably expressed in root.Treatment of M.truncatula seedlings with synthetic PSK-αpeptide significantly promoted root elongation.In addition,expression analysis of downstream genes by RNA-seq and qRT-PCR assays suggested that PSK-αsignaling might regulate cell wall structure via PMEI-PME module to promote root cell growth.Taken together,our results shed light on the mechanism by which PSK-αpromotes root growth in M.truncatula,providing a new resource for improvement of root growth in agriculture.展开更多
基金This work is supported by the National Natural Science Foundation of China(31500197).
文摘Phytosulfokine-α(PSK-α),a sulfated pentapeptide with the sequence YIYTQ,is encoded by a small precursor gene family in Arabidopsis.PSK-αregulates multiple growth and developmental processes as a novel peptide hormone.Despite its importance,functions of PSK-αin M.truncatula growth remains unknown.In this study,we identified five genes to encode PSK-αprecursors in M.truncatula.All of these precursors possess conserved PSK-αsignature motif.Expression pattern analysis of these MtPSK genes revealed that each gene was expressed in a tissue-specific or ubiquitous pattern and three of them were remarkably expressed in root.Treatment of M.truncatula seedlings with synthetic PSK-αpeptide significantly promoted root elongation.In addition,expression analysis of downstream genes by RNA-seq and qRT-PCR assays suggested that PSK-αsignaling might regulate cell wall structure via PMEI-PME module to promote root cell growth.Taken together,our results shed light on the mechanism by which PSK-αpromotes root growth in M.truncatula,providing a new resource for improvement of root growth in agriculture.