b*z
发帖数: 48 | 1
yes/no.
a gene directs the synthesis of one polypeptide. a protein may
contain more than two different polypeptides and require more
than two genes.
in some cases a gene may contain more than two introns (inter-
rupted sequences) and exon (expressed sequences). an RNA
transcribed from such a gene may undergo splicing, that is, the
re-combination of introns and exons, resulting several mRNAs from
one single gene. these mRNAs may then be translated into a group
of proteins. usually such proteins | n*******e
发帖数: 27 | 2 my understanding, for the 1st one, alternative splicing of a specific mRNA
will result in a totally different polypeptide. meanwhile, selection of
start codon will lead to differnt translated protein of a spliced mRNA.
it could be developmental-specific or tissue-specific. i guess it makes
the cell not overburdened with too much information. and it helps to explain
why there are quite less genes than we have expected, yet the network
produces such a complex organism in the world. the second ques |
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