Cloning of a pea cDNA encoding a polypeptide of the light-harvesting complex associated with photosystem I using a monoclonal antibody.
A monoclonal antibody (MAb UB42) is described that binds to thylakoids in pea chloroplasts, as shown by EM-immunogold labelling. The antibody recognised proteins of ca. 23-29 kDa in western blots of a pea leaf homogenate. A cDNA library was prepared from pea epidermal cells in the vector lambda ZAP II, and immunoscreening of the library with UB42 led to the isolation of a clone, pUB42. This was sequenced and had an open reading frame of 269 codons encoding a predicted polypeptide of 28.9 kDa. The sequence showed extensive homology with three closely related polypeptides belonging to a family of chlorophyll a/b-binding proteins from the light harvesting complex of photosystem I (LHCI). Collectively, the results suggest that MAb UB42 recognises an epitope on the type II chlorophyll a/b-binding protein from LHCI and that clone pUB42 encodes this protein.
Cannell
M E
ME
School of Biological Sciences, University of Birmingham, UK.
Mitchell
A J
AJ
McCready
S
S
Callow
J A
JA
Green
J R
JR
D000595:Amino Acid Sequence; D000911:Antibodies, Monoclonal / Q000276:immunology*; D003001:Cloning, Molecular; D018076:DNA, Complementary; D006868:Hydrolysis; D045342:Light-Harvesting Protein Complexes; D008969:Molecular Sequence Data; D018532:Pisum sativum / Q000235:genetics*; D045322:Photosynthetic Reaction Center Complex Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D045331:Photosystem I Protein Complex; D021382:Protein Sorting Signals / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
D000911:Antibodies, Monoclonal; D018076:DNA, Complementary; D045342:Light-Harvesting Protein Complexes; D045322:Photosynthetic Reaction Center Complex Proteins; D045331:Photosystem I Protein Complex; D021382:Protein Sorting Signals