Figure 2.

RT-PCR and northern analysis of tRNA^Asp(GUC) in A. pernix. (a) Expression analysis of mature tRNA^Asp(GUC) (Mat), 5' half of pre-tRNA^Asp(GUC) (5' h), and 3' half of pre-tRNA^Asp(GUC) (3' h) using RT-PCR. M represents the 10-bp DNA ladder. The band sizes correspond to the sizes of the PCR products based on selected primers, but not the transcript sizes of the mature tRNA and the halves. Negative controls without reverse transcriptase (RT (-)) displayed no PCR products in comparison. (b) Northern analysis of tRNA^Asp(GUC) using radiolabeled DNA probe that spans the mature tRNA^Asp(GUC) and the region between the two fragments. The mature tRNA, 5' half transcript and the 3' half transcript are as marked. No expression was found corresponding to the 199-nucleotide transcript originally predicted as pre-tRNA^Asp(GUC) with a 121-nucleotide intron. Bands at approximately 90 nucleotides and 125 nucleotides are expected due to cross-hybridization of highly similar tRNA sequences in other tRNA transcripts. M1 and M2 represent the 10-bp and 100-bp RNA ladders, respectively.