Babiychuk E, Schantz R, Cherep N, Weil JH, Gleba Y, Kushnir S (1995) Alterations in chlorophyll a/b binding proteins in Solanaceae cybrids
Institute of Cell Biology and Genetic Engineering, Kiev, Ukraine.
In this study we have constructed a number of plants (cybrids), in which the nuclear genome of Nicotiana plumbaginifolia is combined with the plastome of Atropa belladonna, or the nuclear genome of N. tabacum with plastomes of Lycium barbarum, Scopolia carniolica, Physochlaine officinalis or Nolana paradoxa. Our biochemical and immunological analyses prove that in these cybrids the biogenesis of the chlorophyll a/b binding proteins (CAB) of the light harvesting complex II (LHCII) is altered. Besides normal sized CAB polypeptides of 27, 25.5 and 25 kDa, which become less abundant, the cybrids analyzed have additional polypeptides of 26, 24.5 and 24 kDa. Direct protein micro-sequencing showed that at least two truncated 26 kDa CAB polypeptides in plant cells containing a nucleus of N. plumbaginifolia and plastids of A. belladonna are encoded by the type 1 Lhcb genes. These polypeptides are 11-12 amino acids shorter at the N-terminus than the expected size. Based on the available data we conclude that the biogenesis of the LHCII in vivo may depend on plastome-encoded factor(s). These results suggest that plastome-encoded factors that cause specific protein degradation and/or abnormal processing might determine compartmental genetic incompatibility in plants.
Keywords: Amino Acid Sequence; Carrier Proteins, chemistry/genetics/metabolism; Cell Compartmentation; Cell Nucleus, genetics; Chimera; Chloroplasts, genetics; Gene Expression; Genes, Plant; Genetic Variation; Hybrid Cells; Light-Harvesting Protein Complexes; Molecular Sequence Data; Multigene Family; Photosynthetic Reaction Center Complex Proteins, chemistry/genetics/metabolism; Photosystem II Protein Complex; Plant Proteins; Plants, Toxic; Plants, genetics; Sequence Analysis; Sequence Homology, Amino Acid; Tobacco, genetics