Comparative analysis of the GATA transcription factors in seven Ipomoea species

The GATA transcription factors regulate plant growth, development, and stress responses, but our knowledge of their functions in sweetpotato and related <i>Ipomoea</i> species remains limited. Through analytical methods of bioinformatics, this study identified 410 <i>GATA</i> genes across seven sequenced <i>Ipomoea</i> species: sweetpotato (158), <i>I. trifida</i> (54), <i>I. triloba</i> (62), <i>I. nil</i> (39), <i>I. purpurea</i> (32), <i>I. cairica</i> (32), and <i>I. aquatica</i> (33). Phylogenetic analysis revealed that these <i>GATA</i> genes clustered into four distinct subfamilies (I-IV). Chromosomal mapping showed an uneven distribution pattern, with complete absence of <i>GATA</i> genes on certain chromosomes in each species. Duplication analysis indicated differential expansion mechanisms: tandem duplications primarily drove <i>GATA</i> gene expansion in <i>I. triloba</i>, <i>I. trifida</i>, and <i>I. nil</i>, whereas segmental duplications were predominant in sweetpotato and <i>I. cairica</i>. Promoter analysis identified multiple stress-responsive <i>cis</i>-regulatory elements, including ABRE, ARE, CGTCA-motif, GC-motif, LTR, MBS, TCA-element, TC-rich repeats, and TGACG-motif. Expression profiling under various stresses (salt, drought, <i>Ceratocystis fimbriata</i> and <i>Ditylenchus destructor)</i> detected 29-60 differentially expressed <i>GATA</i> genes (DEGs). Three representative DEGs (<i>IbGATA33</i>, <i>IbGATA38</i>, and <i>IbGATA126</i>) were validated by qRT-PCR, with results corroborating the transcriptome data. This study may contribute to further understanding of the evolution and function of <i>GATA</i> genes among the <i>Ipomoea</i> species, including sweetpotato.