Gene Annotation: Case 2
(ARF = alternate reading frame) tumor suppressor region on
the short arm of chromosome 9 produces two mRNA transcripts through alternative
-splicing (intra-molecular splicing) that encode two divergent products,
the proteins p16
. Both play important, though very different,
roles in cell growth, survival and senescence. The two transcripts have different
first coding exons but share the coding sequences of exon 2 and 3. However, the
presence of different first exons in the two transcripts causes exons 2 and 3 to
be read in different reading frames. Hence there is no amino acid identity between
the resulting proteins.
. Exons are shown as boxes, introns as line. Shaded regions of
exons are translated, white regions untranslated.
Would you describe this case as one in which
more than one
involved in generating the final transcript/s and/or the polypeptide/s that result
from the process described?
Clearly one gene
Probably only one gene
Probably more than one gene
Clearly more than one gene
How appropriate are the following descriptions of this case? (If alphabetic letters
are used to mark a RNA segment, we are referring to the corresponding DNA sequence.)
One gene: A to F
Two genes: A to F and B to F
Are there any other specific names you would use for any of the regions of the
sequence in this case?
If the case description does not provide you with the information you need to reply,
please indicate what else you would need to know.