High impact information on psbA

• A detailed analysis of the structure and the frequency of the pre-mRNAs of the psbA gene showed that the four introns are neither spliced out in a strictly random way, nor in a 5'-3' or 3'-5' direction [1].
• The nucleotide sequence of 3324 bp of Eco I, containing the psbA locus, has been determined [2].
• This locus encodes a polypeptide of 345 amino acids which is co-linear with, and has 86% derived amino acid sequence homology to sequences derived from four higher plants chloroplast psbA loci [2].
• The psbA gene is the coding locus for a polypeptide of 32 kilodaltons that is involved in electron transport through photosystem II [3].
• The majority of known group II introns are from chloroplast genomes, yet the first self-splicing group II intron from a chloroplast gene was reported only recently, from the psbA gene of the euglenoid, Euglena myxocylindracea [4].

Biological context of psbA

• The Euglena psbA gene contains four introns of size 435, 443, 434, and 617 bp [2].
• The psbA gene of DCMU-resistant Euglena gracilis has an amino acid substitution at serine codon 265 [5].

Analytical, diagnostic and therapeutic context of psbA

• The structure and the frequency of the pre-mRNAs of the psbA gene (the gene for the 32-kd protein of photosystem II), which is split by four introns in Euglena chloroplasts was analysed by electron microscopy [1].

References