SlJAZ2 Overexpression Accelerates Reproductive Growth in Tomato

JAZ (Jasmonate ZIM-domain) proteins are important repressors in JA signaling pathway. JAZs take part in various developmental processes as well as in resistance to biotic and abiotic stresses in Arabiodopsis. However, in tomato, the studies on these JAZs are rare, especially on their roles in plant growth and development. The research team of Xiaohui Yu from Chongqing University in China isolated and studied a tomato JAZ gene, SlJAZ2.

Tomato plants overexpressing SlJAZ2 exhibited quicker leaf initiation, reduced plant height and internode length. The transgenic tomatoes also had decreasing trichomes, earlier lateral bud emergence and advanced flowering transition. Further experiments showed that pith cells in transgenic plant stems were much smaller than wildtypes as a result of the downregulation of genes related to cell elongation and gibberellin synthesis.

Genes controlling trichome formation were also inhibited. Furthermore, there was earlier flower initiation in transgenic plants, and the genes controlling flowering time were upregulated significantly after SlJAZ2 overexpression.

These results suggest that SlJAZ2 could be related to the initiation of the plants' reproductive stage as its overexpression accelerated the plants' transition from vegetative to reproductive growth.

For more on this study, read the article in Plant Science.