Figure 2. 2 -A. Transcription and translation maps of adenovirus type 2. Ad2 
and Ad5 (the base virus for AdCFTR) belong to the same subgroup and have 
94. 7X nucleic acid sequence identify. The left strand (5' to 3') and right 
strand (3' to 5 ' ) are divided into 100 map units (m.u.). The early mRNAs 
(Ela, Elb , some of E2A, most of E2B, E3 and E4) are indicated as thick 
arrows. The intermediate mRNAs expressed early and late (some E2a, some E2b 
and IX) are indicated as thin arrows. The late mRNAs (LI, L2 , L3 , L4 , and 
L5) are indicated as open arrows. The direction of transcription is indi- 
cated by the arrows. The capped 5' ends of the mRNA (indicated by a bracket 
to the left or right of the start of the arrow) indicate the position of 
the transcriptional promoters, and the end of the arrowheads indicate the 
3' ends of the mRNA. Gaps indicate intervening sequences removed by splic- 
ing to form the mature cytoplasmic mRNA. The L1-L5 mRNAs all originate with 
the same tripartite leader sequences 1, 2, and 3 (except for one LI mRNA 
which uses the fourth leader segment "i"). Also indicated are most of the 
structural and nonstructural proteins comprising the virion. For further 
details see Berkner, 1988; Ginsberg, 1984; Horwitz , 1990a. 
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