The NtAN3 gene plays a key role in increasing tobacco leaf area

Abstract

Tobacco (Nicotiana tabacum L.) is an important cash crop, and the size of its leaves significantly influences both yield and quality. However, previous research often focused on cultivation measures to enhance yield and quality, while the study of the structure and function of genes at the molecular level has been overlooked. We measured leaf area of NtAN3 overexpression mutant, silencing mutant, and wild-type, We measured the leaf areas of NtAN3 overexpressing mutants, silenced mutants, and wild type. Compared with the wild type, the leaf area of the overexpressing mutant was significantly increased, and the leaf area of the silenced mutant was significantly decreased, indicating that NtAN3 plays a role in regulating the leaf area of tobacco. To understand the molecular mechanisms, we selected two mutants, G27 and M21, which have significant differences in leaf area, and their parents for transcriptome analysis. There were 1,697 differentially expressed genes in WT vs G27 and 2,388 differentially expressed genes in WT vs M21. The enrichment analysis of these differentially expressed genes indicated that “carbohydrate metabolism” was associated with leaf area development. We focused on the analysis of the pathways of starch and sucrose metabolism and galactose metabolism, indicating that the high expression of genes in these pathways may enhance leaf area development. In addition, Nitab4.5_0000564g0140, Nitab4.5_0006318g0030, and Nitab4.5_0002093g0100 may be genes involved in tobacco leaf area growth. Transcriptome analysis have deepened our understanding of the regulatory network of tobacco leaf area development, and provided new ideas for molecular breeding of tobacco leaf area and improvement of tobacco leaf yield.