Related Experiment Videos
Soybean ENOD40 encodes two peptides that bind to sucrose synthase
Horst Rohrig1, Jurgen Schmidt, Edvins Miklashevichs
1Max-Planck-Institut für Züchtungsforschung, Carl-von-Linné-Weg 10, 50829 Cologne, Germany. Roehrig@mpiz-koeln.mpg.de
Summary
ENOD40 gene products, small peptides A and B, are translated from short ORFs in legumes. These peptides bind to nodulin 100, a sucrose synthase subunit, suggesting a role in nitrogen-fixing nodule sucrose metabolism.
Area of Science:
- Plant Molecular Biology
- Legume Symbiosis
- Biochemistry
Background:
- ENOD40 gene expression is crucial during early root nodule organogenesis in legumes.
- Homologs of ENOD40 in nonlegumes indicate a broader biological role beyond legumes.
- ENOD40 mRNA contains a conserved 5' region encoding small peptides.
Purpose of the Study:
- To investigate the translation and function of ENOD40 gene products.
- To identify proteins interacting with ENOD40-derived peptides.
- To elucidate the role of ENOD40 peptides in nitrogen-fixing nodules.
Main Methods:
- In vitro translation of soybean ENOD40 mRNA using wheat germ extracts.
- Western blotting to detect ENOD40 peptides in soybean nodules.
- Affinity purification and peptide mass fingerprinting to identify binding proteins.
Main Results:
- Soybean ENOD40 mRNA 5' region (region I) encodes two small peptides (12 and 24 aa) from overlapping ORFs.
- Peptide B was detected in nodules; both peptides bind to a 93-kDa protein.
- The binding protein was identified as nodulin 100, a subunit of sucrose synthase.
Conclusions:
- ENOD40 peptides are directly translated from polycistronic eukaryotic mRNA.
- ENOD40 peptides bind specifically to nodulin 100 (sucrose synthase subunit).
- ENOD40 peptides likely regulate sucrose utilization in nitrogen-fixing legume nodules.