How U can read map of DNA & some questions - recognize Map (Feb/24/2006 )

Hello

the first problem , when read map of DNA sequence, is presence of ( - ) sign what dose this mean ?

second : the sequence present in any article represent DNA sequence of gene , However, If u look to it u will find this the sequence is for mRNA and u find ( T) written in place of ( U) ?

3- what is " stacking region " ?

4- should Methionine begin the preotein sequence ?

I hope who Know tell me
Ahmad

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( - ) sign means upstream region.
ATG/methionine is the start codon of DNA/protein sequence

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can u tell me upstream start from ? to ? .?

what about stacking region ?

To who know , reply

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Now, Al-hamd le allah ,, I found some answers to whom it may concern

about Upstream/Downstream: refer to

http://seqcore.brcf.med.umich.edu/doc/educ...ry/mbgloss.html


In an RNA, anything towards the 5' end of a reference point is "upstream" of that point. This orientation reflects the direction of both the synthesis of mRNA, and its translation - from the 5' end to the 3' end. In DNA, the situation is a bit more complicated. In the vicinity of a gene (or in a cDNA), the DNA has two strands, but one strand is virtually a duplicate of the RNA, so it's 5' and 3' ends determine upstream and downstream, respectively. NOTE that in genomic DNA, two adjacent genes may be on different strands and thus oriented in opposite directions. Upstream or downstream is only used on conjunction with a given gene


about minus
( transcription start )
( upstream) |
-?............................-1+1+2.................
xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx ---- sequence

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