SEQUENCE-ANALYSIS OF THE 2ND LARGEST SUBUNIT OF TOMATO RNA-POLYMERASE-II

We have cloned and sequenced the cDNA encoding the open reading frame of the mRNA of the second largest subunit of RNA polymerase II, or RPB 2, of tomato. The mRNA is transcribed from a single-copy gene in the t omato genome and the transcript size of the gene was measured as 4.2 k b by northern analysis. From the deduced amino acid sequence of 1191 r esidues, a protein of M(r) 135 000 with an isoelectric point of pH 7.9 was predicted. Alignment of the tomato RPB2 protein sequence with tho se of the homologous subunits in Arabidopsis, man, Drosophila and yeas t showed considerable sequence identity.