5 psbA region

Comparison of deduced amino acid sequences from psbA genes. Note the conservation of the PEST-1ike region contiguous with the a-helix-destabilizing, primary cleavage domain in the 32kDa protein. The arrow indicates the probable site where the precursor piece on the carboxy-terminus is cleaved (22). psbA sequences were compiled as follows (1) Anacystis nidulans copy I, and (2) copy II/III (41). 

Staub, J.M. and P. Maliga, Accumulation of D1 polypeptide in tobacco plastids is regulated via the untranslated region of the psbA mRNA. EMBO J, 1993 12(2) 601-606. 

Kress, W.J. and Erickson, D.L., A two-locus global DNA barcode for land plants The coding rbcL gene complements the non-coding tmH-psbA spacer region, PloS One, 2(6), e508, 2007. 

Another novel mutant was identified, when field accessions of Poa annua with resistance to PS II inhibitors, collected in Western Oregon, were analyzed after amplification of the herbicide-binding region (933 base pair fragment) of the chloroplast psbA gene using PGR. 

The chloroplast genes psbA and psbD encode the reaction centre polypeptides D1 and D2. The genes encode related polypeptides of 353 amino acid residues which are predicted to form five membrane-spanning regions (Fig. 2) similar to the L and M subunits of the bacterial reaction centre. However it is probable that the mature D1 polypeptide is smallo than die mature D2 polypeptide due to Ae removal of 12-16 residues at die C-terminus of DP. Both polypeptides are modified at the IV-terminus by the removal of W-formyl methionine andN-acetylation of the threonine residues. Both the D1 and D2 polypeptides may be phosphorylated on the JV-terminal threonine residue. ... 

Figure 3 Northern blot analyses of RNA isolated from S. 6803 wild type (A) and mutant S. 6803 SF (B). In the left panel the probe was a mixture of the psbA-1 and psbA-2 genes from S. 6803, in the middle panel the psbA gene from A. hybridus and in the right panel the 5 region of the rbcl gene from S. 6803.

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