| Comments |
P.3 left column 4th paragraph:"Assuming that ribonucleotides are efficiently recycled (meaning that, because nuclease activity does not consume ATP, the cost associated with turnover consists of the two phosphates needed to recharge them discussed below), the total number of de novo nucleotide syntheses associated with a particular gene is a function of the average steady-state number of mRNAs (Nr) and the length of the mature mRNA (Lr,mat) (including the polyadenylation tail, which when present often has a length on the order of ∼100 nucleotides), yielding a total cost of biosynthesis of 46 ·NrLr,mat P." P.3 left column 4th paragraph:"The latter includes introns, the difference between the initial (∼250 nucleotides) and mature (∼100 nucleotides) length of the poly(A) tail, and any transcriptional read-through past the termination point, which can also be a few hundred nucleotides in length in some eukaryotes." |