Characterization and transformation of a novel ABI3/VP1-1 gene from hot pepper to enhance waterlogging tolerance

Abstract

The ABI3/VP1 proteins are critical in regulating plant growth and resisting stress. This study successfully cloned ABI3/VP1 from waterlogging tolerant pepper (Capsicum annuum) 'ZHC2'. This gene contains a 1017-bp open reading frame, encoding 338 amino acids, and is most closely related to the protein C. annuum XP 016577237.2. CaABI3/VP1–1 was located in the nucleus. This gene was successfully independently transformed into hot peppers ‘ZHC1’ and ‘DFZJ’, as well as Nicotiana benthamiana. CaABI3/VP1 overexpression in hot peppers ‘ZHC1’ and ‘DFZJ’, as well as N. benthamiana promoted the growth of lateral roots, adventitious roots, and stems, as well as the lodging-resistant ability. In addition, the degree of leaf wilting was lower than that of wild-type plants. In general, the water, soluble protein, and proline contents, stomatal density, and catalase activity increased, but H2O2 and malondialdehyde levels decreased. The transcriptomic analysis of the ‘DFZJ’ overexpression line revealed that the “ribosome”, “MAPK signaling pathway-plant”, “plant hormone signal transduction”, “plant-pathogen interaction”, “arginine and proline metabolism”, and “peroxisome” pathways were enriched. LOC107844566, LOC107843480, LOC107879909, LOC107851756, LOC107843452, and LOC107851705 are downstream genes that may be regulated by CaABI3/VP1–1. The physiological and biochemical data were consistent with the transcriptome results. Therefore, CaABI3/VP1–1 should be involved in the waterlogging tolerance of peppers, which would assist in their waterlogging-tolerant breeding.