JBC, Vol. 254, Issue 24, 12306-12309, Dec, 1979
Isolation of yeast tRNALeu genes. DNA sequence of a cloned tRNALeu3 gene
A. Venegas, M. Quiroga, J. Zaldivar, W. J. Rutter and P. Valenzuela
A library of cloned yeast DNA fragments generated by digestion of yeast DNA
with the restriction endonuclease Bam HI has been screened by colony
hybridization to total yeast [32P]tRNA. Four hundred colonies carrying
yeast tRNA genes were isolated. By hybridization to 125I-tRNALeu3, we have
isolated from this collection 14 colonies carrying fragments containing
yeast tRNALeu genes. The size of the yeast Bam HI inserts ranged from 2.45
x 10(6) to 14 x 10(6) daltons. One of these fragments was mapped in detail
by restriction endonuclease digestion and hybridization to 125I-tRNALeu3.
The presence of a tRNALeu3 gene was confirmed by DNA sequence. The results
indicate that the tRNALeu3 coding region is not co-linear with the
tRNALeu3. An intervening tract of 33 base pairs interrupts the coding
sequences 1 base pair past the anticodon coding region. The putative
structure of a tRNALeu3 precursor is deduced in which the anticodon base
pairs with residues from the intervening sequence.