Genome-Wide Characterization, Identification and Expression Profile of MYB Transcription Factor Gene Family during Abiotic and Biotic Stresses in Mango (Mangifera indica)

Abstract

Mango (<i>Mangifera indica</i>) is an economically important fruit tree, and is cultivated in tropical, subtropical, and dry-hot valley areas around the world. Mango fruits have high nutritional value, and are mainly consumed fresh and used for commercial purposes. Mango is affected by various environmental factors during its growth and development. The <i>MYB</i> transcription factors participates in various physiological activities of plants, such as phytohormone signal transduction and disease resistance. In this study, 54 <i>MiMYB</i> transcription factors were identified in the mango genome (371.6 Mb). A phylogenetic tree was drawn based on the amino acid sequences of 222 MYB proteins of mango and Arabidopsis. The phylogenetic tree showed that the members of the mango MYB gene family were divided into 7 group, including Groups 1, -3, -4, -5, -6, -8, and -9. Ka/Ks ratios generally indicated that the <i>MiMYBs</i> of mango were affected by negative or positive selection. Quantitative real-time PCR showed that the transcription levels of <i>MiMYBs</i> were different under abiotic and biotic stresses, including salicylic acid, methyl jasmonate, and H₂O₂ treatments, and <i>Colletotrichum gloeosporioides</i> and <i>Xanthomonas campestris</i> pv. <i>mangiferaeindicae</i> infection, respectively. The transcript levels of <i>MiMYB5</i>, <i>-35</i>, <i>-36</i>, and <i>-54</i> simultaneously responded positively to early treatments with salicylic acid, methyl jasmonate, and H₂O_2. The transcript level of <i>MiMYB54</i> was activated by pathogenic fungal and bacterial infection. These results are beneficial for future interested researchers aiming to understand the biological functions and molecular mechanisms of <i>MiMYB</i> genes.