Genome-Wide Identification of the BTB Domain-Containing Protein Gene Family in Pepper (Capsicum annuum L.)

TL;DR

This study identifies 72 BTB domain-containing genes in pepper and explores their expression and localization, offering insights into their biological roles.

Contribution

The first genome-wide identification and functional analysis of the BTB gene family in pepper (Capsicum annuum L.).

Findings

Seventy-two CaBTB genes were identified in the pepper genome.

CaBTB25 is highly expressed in leaves and contains light-responsive promoter elements.

CaBTB25 localizes to the nucleus and lacks transcriptional activation.

Abstract

Pepper (Capsicum annuum L.), recognized as a globally preeminent vegetable, holds substantial economic and nutritional value. The BTB (broad-complex, tramtrack, and bric-a-brac) family of proteins, characterized by a highly conserved BTB domain, also denoted as the POZ domain, are intricately involved in a diverse array of biological processes. However, the existing corpus of research regarding pepper BTB genes remains relatively meager. In this study, a total of 72 CaBTB gene members were meticulously identified from the entire genome of pepper. Phylogenetic analysis illuminated the presence of conspicuous collinear relationships between the CaBTB genes and those of its closely affiliated species. Gene expression profiling and RT-qPCR analysis revealed that multiple CaBTB genes exhibited pronounced differential expression under diverse treatment regimens. Expression pattern analysis unveiled that CaBTB25 manifested a remarkably elevated abundance in leaves. Moreover, its promoters were replete with an abundance of light-responsive cis-elements. Our comprehensive and in-depth explorations into subcellular localization revealed that CaBTB25 was predominantly detected to localize within the nucleus and lacked transcriptional activation. This research provides a crucial theoretical edifice, enabling a more profound understanding of the biological functions of the BTB gene family in pepper, thereby underscoring its potential significance within the intricate network of gene–environment interactions.

Figures