The AP2/ERF family is one of the largest transcription factor families in the plant kingdom. AP2/ERF genes contributing to various processes including plant growth， development， and response to various stresses have been identified. In this study， 175 putative AP2/ERF genes were identified in the latest pepper genome database and classified into AP2， RAV， ERF， and Soloist subfamilies. Their chromosomal localization， gene structure， conserved motif， cis-acting elements within the promoter region， and subcellular locations were analyzed. Transient expression of CaAP2/ERF proteins in tobacco revealed that CaAP2/ERF064， CaAP2/ERF109， and CaAP2/ERF127 were located in the nucleus， while CaAP... More
The AP2/ERF family is one of the largest transcription factor families in the plant kingdom. AP2/ERF genes contributing to various processes including plant growth， development， and response to various stresses have been identified. In this study， 175 putative AP2/ERF genes were identified in the latest pepper genome database and classified into AP2， RAV， ERF， and Soloist subfamilies. Their chromosomal localization， gene structure， conserved motif， cis-acting elements within the promoter region， and subcellular locations were analyzed. Transient expression of CaAP2/ERF proteins in tobacco revealed that CaAP2/ERF064， CaAP2/ERF109， and CaAP2/ERF127 were located in the nucleus， while CaAP2/ERF171 was located in the nucleus and cytoplasm. Most of the CaAP2/ERF genes contained cis-elements within their promoter regions that responded to various stresses (HSE， LTR， MBS， Box-W1/W-box， and TC-rich repeats) and phytohormones (ABRE， CGTCA-motif， and TCA-element). Furthermore， RNA-seq analysis revealed that CaAP2/ERF genes showed differential expression profiles in various tissues as well as under biotic stresses. Moreover， qRT-PCR analysis of eight selected CaAP2/ERF genes also showed differential expression patterns in response to infection with Phytophthora capsici (HX-9) and in response to phytohormones (SA， MeJA， and ETH). This study will provide basic insights for further studies of the CaAP2/ERF genes involved in the interaction between pepper and P. capsici.
