Main content area

Transgenic pepper plants carrying RNA interference constructs of CaCOI1 gene show severe abnormality

Hu, Tingzhang, Yang, Yongwei, Zeng, Hua, Hu, Zongli, Chen, Zaigang, Chen, Guoping, Wu, Yingmei
Molecular breeding 2013 v.31 no.4 pp. 971-979
RNA interference, amino acids, complementary DNA, flowers, fruits, genes, isoelectric point, molecular weight, open reading frames, pepper, peppers, phenotype, proteins, quantitative polymerase chain reaction, reverse transcriptase polymerase chain reaction, seeds
Coronatine insensitive 1 (COI1) is a key regulator in the jasmonate signaling pathway, which plays a central role in jasmonate signaling by forming SCF complexes in the ubiquitination pathway. In this study, the full-length cDNA of CaCOI1 was isolated from chili pepper by reverse transcription PCR. CaCOI1 contains a 1,812-bp open reading frame encoding 603 amino acids. The calculated molecular weight and isoelectric point of the deduced CaCOI1 protein are 68.35 and 6.32 kDa, respectively. CaCOI1 protein shares extensive homology with COI1 proteins of other plant species, and has been predicted to possess a F-box of 30 amino acid residues at the N-terminal and six leucine-rich repeat domains at the C-terminal. Quantitative real-time PCR analysis showed that CaCOI1 can be expressed in detected tissues and organs. The expression level of CaCOI1 in flowers was dramatically increased 2.8–5.4 times higher than that in other tissues and organs. The transgenic suppression of the CaCOI1 gene in the transgenic pepper plants allowed us to test the role of the CaCOI1 protein. CaCOI1-silenced pepper plants showed a severely abnormal phenotype. Compared with wild-type peppers, the CaCOI1-silenced pepper plants suffered from dwarfism with abnormal fruits, and bore misshapen and sterile seeds. The data indicate that CaCOI1 plays an important role in the developmental processes of pepper plants and fruits.