Genes involved in the deformations of the shoot apical meristem in somatic embryos of Capsicum chinense Jacq.

ABSTRACT

Somatic embryos (SE) of habanero pepper (Capsicum chinense Jacq.) represent persistent deformations in the shoot apical meristem (SAM), which inhibits their capacity to form organs and subsequently plants. In dicotyledonous plants, SAM is formed in the apex, between cotyledons and it plays a central role in postembryonic shoot organ formation. Based on the previous knowledge on the role of some families of gene in the formation, organization and maintenance of the SAM, the expression patterns of WUS, WOX2, NAM, STM, PIN1 and PIN7 genes were analysed, which would allow us to elucidate the possible implication of these genes in SAM deformations in the SE of C. chinense. The results show that the expression patterns of STM and PIN1 in the SE were completely opposite to the respective expression pattern obtained in zygotic embryos (ZE). Moreover, NAM and PIN7 showed an over accumulation of transcripts in SE, compared with ZE. This is the first time in the genus Capsicum that alterations in the expression pattern of key genes of the SE development are reported, as well as its possible implication in the persistent deformations of the SAM.