LAUSR

The plant hormone abscisic acid (ABA) plays an important role in many aspects of plant growth and development, and a growing number of evidences show that ABA may play an important role in the development of tomato pollen development. To further analyze the role of ABA in the development of tomato pollen, the SlNCED1 gene encoding 9-cis-epoxycarotenoid dioxygenase (NCED), a key enzyme in the ABA biosynthesis, was suppressed in tomato plants by transformation with RNA interference (RNAi). Endogenous ABA content and SlNCED1 transcript levels in the transgenic anther were down-regulated to between 20 and 55% of the levels measured in the wild-type anther. The significant reduction of NCED activity led to a down-regulation in the transcription of specific genes positively related to anther development in tomato, such as TomA92b9, TomA108, SlbHLH080 and 5B-CRP. However, leading to an up-regulation in the transcription of specific genes negatively related to anther development in tomato, such as adh-3a, LAT58, LePro1 and SlPMEI. This resulted in abnormal anther development, which led to the development of a large number of abnormal pollens. In conclusion, ABA affects pollen maturation by regulating the expression of anther-specific genes.