Proteomic and phosphoproteomic determination of ABA's effects on grain-filling of Oryza sativa L. inferior spikelets.
Cultivars of rice (Oryza sativa L.), especially the large-spikelet-type, often fail to achieve the high yield potential due to poor grain-filling of their inferior (late-flowering) spikelets. The superior (early-flowering) spikelets normally contain more abscisic acid (ABA) than the inferior spikelets. It was speculated that ABA might play a pivotal role in the grain-filling of inferior spikelets. To understand the molecular regulation involved in this process, we employed the 2-D gel-based comparative proteomic and phosphoproteomic analyses to search for differentially expressed proteins in the inferior spikelets under exogenous ABA treatment. A total of 111 significantly differential proteins and 31 phosphoproteins were found in the inferior spikelets after treatment. Among them, 100 proteins and 23 phosphoproteins were identified by using MALDI-TOF/TOF MS. In addition, the gene expression patterns of the inferior spikelets were confirmed with RT-PCR. These differentially expressed proteins are active in defense response, carbohydrate, protein, amino acid, energy and secondary metabolisms, as well as cell development and photosynthesis. The results suggest that the grain-filling of rice inferior spikelets is regulated by ABA through some proteins and phosphoproteins participating in carbon, nitrogen and energy metabolisms.
Institute of Agricultural Ecology, Fujian Agricultural and Forestry University, Fuzhou, Fujian 35002, People's Republic of China.
Zhixing
Z
Zhang
Jun
J
Chen
Shisheng
S
Lin
Zhong
Z
Li
Ronghuai
R
Cheng
Changxun
C
Fang
Hongfei
H
Chen
Wenxiong
W
Lin
D000040:Abscisic Acid / Q000494:pharmacology*; D002523:Edible Grain / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D012275:Oryza / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010940:Plant Proteins / Q000302:isolation & purification / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D018749:RNA, Plant / Q000032:analysis / Q000235:genetics; D053719:Tandem Mass Spectrometry
D010937:Plant Growth Regulators; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; D000040:Abscisic Acid