Mapping the N-linked glycosites of rice (Oryza sativa L.) germinating embryos.
Germination is a key event in the angiosperm life cycle. N-glycosylation of proteins is one of the most common post-translational modifications, and has been recognized to be an important regulator of the proteome of the germinating embryo. Here, we report the first N-linked glycosites mapping of rice embryos during germination by using a hydrophilic interaction chromatography (HILIC) glycopeptides enrichment strategy associated with high accuracy mass spectrometry identification. A total of 242 glycosites from 191 unique proteins was discovered. Inspection of the motifs and sequence structures involved suggested that all the glycosites were concentrated within [NxS/T] motif, while 82.3% of them were in a coil structure. N-glycosylation preferentially occurred on proteins with glycoside hydrolase activities, which were significantly enriched in the starch and sucrose metabolism pathway, suggesting that N-glycosylation is involved in embryo germination by regulating carbohydrate metabolism. Notably, protein-protein interaction analysis revealed a network with several Brassinosteroids signaling proteins, including XIAO and other BR-responsive proteins, implying that glycosylation-mediated Brassinosteroids signaling may be a key mechanism regulating rice embryo germination. In summary, this study expanded our knowledge of protein glycosylation in rice, and provided novel insight into the PTM regulation in rice seed germination.
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Jiezheng
J
Ying
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Juan
J
Zhao
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Yuxuan
Y
Hou
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Yifeng
Y
Wang
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Jiehua
J
Qiu
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Zhiyong
Z
Li
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Xiaohong
X
Tong
Jingjie PTM-Biolabs, Hangzhou, P.R. China.
Zhaomei
Z
Shi
Jingjie PTM-Biolabs, Hangzhou, P.R. China.
Jun
J
Zhu
State Key Lab of Rice Biology, China National Rice Research Institute, Hangzhou, P.R. China.
Jian
http://orcid.org/0000-0003-2804-0162
J
Zhang
D000595:Amino Acid Sequence; D060406:Brassinosteroids / Q000737:chemistry / Q000378:metabolism; D050260:Carbohydrate Metabolism; D002473:Cell Wall / Q000378:metabolism; D004721:Endoplasmic Reticulum / Q000378:metabolism; D018525:Germination; D006023:Glycoproteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D006031:Glycosylation; D053858:Metabolic Networks and Pathways; D012275:Oryza / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism*; D010449:Peptide Mapping; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D054730:Protein Interaction Domains and Motifs; D011499:Protein Processing, Post-Translational; D015398:Signal Transduction; D013213:Starch / Q000378:metabolism; D013395:Sucrose / Q000378:metabolism
D060406:Brassinosteroids; D006023:Glycoproteins; D010940:Plant Proteins; D013395:Sucrose; D013213:Starch