Abstract
The LBD (Lateral Organ Boundaries Domain) family are a new group of plant-specific genes, which encode a class of transcription factors containing conserved Lateral Organization Boundary (LOB) domains, and play an important role in regulating the adaxial–abaxial polarity of plant leaves. In Arabidopsis thaliana, ASYMMETRIC LEAVES 2 (AS2) has a typical LOB domain and is involved in determining the adaxial cell fate. In this study, we isolated the BcAS2 gene from the pak choi cultivar “NHCC001”, and analyzed its expression pattern. The results showed that the BcAS2 encoded a protein made up of 202 amino acid residues which were located in the nucleus and cytomembrane. The Yeast two-hybrid system (Y2H) assay indicated that BcAS2 interacts with BcAS1-1 and BcAS1-2 (the homologous genes of AS1 gene in pak choi). In the transgenic Arabidopsis thaliana that overexpressed BcAS2 gene, it presented an abnormal phenotype with a curly shape. Taken together, our findings not only validate the function of BcAS2 in leaf development in Arabidopsis thaliana, but also contribute in unravelling the molecular regulatory mechanism of BcAS2, which fulfills a special role by forming complexes with BcAS1-1/2 in the establishment of the adaxial–abaxial polarity of the lateral organs in pak choi.
Highlights
The flat symmetric leaves are essential for plant development as they provide the place for photosynthesis, respiration and other important physiological activities
The online software ProtParam showed that the full length coding sequence (CDS) of BcAS2 encoded 202 amino acid residues with molecular weight of 22.09 kDa and theoretical isoelectric point of 7.1
We found that the protein of 35S:BcAS2-GFP fusions were expressed in the nucleus and cytomembrane mainly (Figure 3), indicating that BcAS2 may function as a transcription factor and as some cytomembrane proteins
Summary
The flat symmetric leaves are essential for plant development as they provide the place for photosynthesis, respiration and other important physiological activities. The initiation and maintenance of SAM requires the normal expression of a highly conserved class of homeodomain transcription factors encoded by class-I KNOX genes, which include four members: SHOOT MERISTEMLESS (STM); BREVIPEDICELLUS (BP); KNAT2 and KNAT6 [5,6,7,8]. The development of leaves will be disrupted if the KNOX genes continue expressing. Hareven’s study demonstrates that there would be super-compound leaves if the KNOX genes overexpressed in tomato [11]. The ectopic expression of KNOX genes in maize presents an abnormal phenotype with distal displacement of sheath and auricle tissue into the blade, and produces deeply serrated or segmented leaves in Arabidopsis thaliana [12,13]. It is a critical event to down regulate KNOX genes in lateral organ primordia for normal leaf development [14]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
