<i>BrrA02.LMI1</i> Encodes a Homeobox Protein That Affects Leaf Margin Development in <i>Brassica rapa</i>
Leaf margin morphology is an important quality trait affecting the commodity and environmental adaptability of crops. <i>Brassica rapa</i> is an ideal research material for exploring the molecular mechanisms underlying leaf lobe development. Here, we identified <i>BrrA02.LMI1</i...
| Main Authors: | , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-09-01
|
| Series: | International Journal of Molecular Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1422-0067/24/18/14205 |
| Summary: | Leaf margin morphology is an important quality trait affecting the commodity and environmental adaptability of crops. <i>Brassica rapa</i> is an ideal research material for exploring the molecular mechanisms underlying leaf lobe development. Here, we identified <i>BrrA02.LMI1</i> to be a promising gene underlying the QTL <i>qBrrLLA02</i> controlling leaf lobe formation in <i>B. rapa,</i> which was detected in our previous study. Sequence comparison analysis showed that the promoter divergences were the most obvious variations of <i>BrrA02.LMI1</i> between parental lines. The higher expression level and promoter activity of <i>BrrA02.LMI1</i> in the lobe-leafed parent indicated that promoter variations of <i>BrrA02.LMI1</i> were responsible for elevating expression and ultimately causing different allele effects. Histochemical GUS staining indicated that <i>BrrA02.LMI1</i> is mainly expressed at the leaf margin, with the highest expression at the tip of each lobe. Subcellular localization results showed that BrrA02.LMI1 was in the nucleus. The ectopic expression of <i>BrrA02.LMI1</i> in <i>A. thaliana</i> resulted in a deep leaf lobe in the wild-type plants, and lobed leaf formation was disturbed in <i>BrrA02.LMI11</i>-downregulated plants. Our findings revealed that <i>BrrA02.LMI1</i> plays a vital role in regulating the formation of lobed leaves, providing a theoretical basis for the selection and breeding of leaf-shape-diverse varieties of <i>B. rapa</i>. |
|---|---|
| ISSN: | 1661-6596 1422-0067 |