Gene Annotation: Case 3
In the sequence complex
-splicing (intra-molecular splicing) creates two mature mRNAs that share
a noncoding exon as a common translation start site but no overlapping coding
sequences, and that encode structurally unrelated proteins (the 259aa protein
and a ubiquitin fusion protein). The entire coding region of the IP259
transcript is found in the first intron of
. Note: There is a very
similar case in the nematode
, where the DNA complex
(also known as
) encodes the structurally unrelated proteins
choline acetyl-transferase and vesicular acetylcholine transporter protein.
In both the Drosophila case we focus on here and the similar nematode case,
the genomic complexes and their products are highly conserved and homologues
are found in nematodes, insects and mammals (incl. humans). In both cases
each individual mRNA transcript can produce only one of the two products.
. 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 C
Two genes: A + B and A + C
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.