Synthesis
of
Genes
for
a
True
Precursor
tRNA - Before Khorana could complete the synthesis of gene for yeast alanyl tRNA in' 1970, as outlined above, it became obvious that tRNA was not the direct product of transcription. Instead a precursor molecule is first synthesized which subsequently, after losing segments of RNA by cleavage, gives rise to tRNA.
Obviously, therefore, the actual gene for yeast alanyl tRNA will be longer than the DNA duplex synthesized by Khorana. In view of this, Khorana subsequently initiated synthesis of a gene for E. coli tyrosine suppressor tRNA precursor. DNA duplex which will give rise to this tRNA precursor, was synthesized in the form of 26 small oligo nucleotide segments.
