Genome-Wide Identification and Expression Analysis of CAMTA Genes in Cassava Under Abiotic Stresses

Cassava (<i>Manihot esculenta</i> Crantz) is a major dual-purpose crop in tropical and subtropical regions, but its growth and yield are significantly constrained by abiotic stresses. Calmodulin-binding transcription activators (CAMTAs) are key regulators involved in plant development and stress responses. In this research, six <i>CAMTA</i> genes (<i>MeCAMTAs</i>) were identified from the first telomere-to-telomere (T2T) genome assembly of cassava, and these genes are distributed on four chromosomes. These genes are divided into three different subfamilies based on phylogenetic relationships. Homology analysis shows that there is one pair of replication gene pairs. Analysis of cis-acting elements reveals that the promoter regions of the <i>MeCAMTA</i> gene family contain cis-acting elements responsive to hormones, abiotic stresses, growth and development, and light. Through analysis of the expression patterns of <i>MeCAMTAs</i> in different tissues, <i>MeCAMTAs</i> are expressed in all tissues, among which <i>MeCAMTA3</i> and <i>MeCAMTA4.1</i> are mainly expressed in stems, while <i>MeCAMTA1</i>, <i>MeCAMTA2</i>, <i>MeCAMTA4.2</i>, and <i>MeCAMTA6</i> are mainly expressed in roots. qRT-PCR analysis shows that <i>MeCAMTAs</i> exhibit dynamic expression patterns under different abiotic stress treatments. Therefore, this study provides a certain reference basis for the research on the abiotic stress response mechanism of cassava and also provides potential genetic resources for the stress-resistant breeding of cassava.