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Farazdaq 02-26-2010 12:56 PM

DNA Sequences
 
TACGATCATAT is an oligonucleotide probe used to construct a cDNA library to study the transcriptome of genetically modified mice.
Which of the following coding strands will correctly hybridize with the probe in question?

A- TACGATCATAT
B- ATATGATCGTA
C- AUGCUAGUAUA
D- GCATATACGCG
E- AUAUGAUCGUA

Aditya 02-26-2010 01:23 PM

C
 
C IS the ans i guess

GNND85 02-26-2010 01:38 PM

It's not C
 
Quote:

Originally Posted by Aditya (Post 5557)
C IS the ans i guess

So contains uracil, DNA template strands do not contain Uracil
I think the answer is B

Aditya 02-26-2010 01:59 PM

ooops
 
yea a blunder, i made...havent read mol biochemistry yet..

ashishkabir 03-05-2010 09:57 PM

Agreed - i think it's B too...

bianca 03-14-2010 11:11 PM

B, cDNA complementery & antiparallel. Match the nucleotide starting from the back, just a hit. It works for me.

GNND85 03-15-2010 06:34 AM

Yes
 
Quote:

Originally Posted by bianca (Post 6211)
B, cDNA complementery & antiparallel. Match the nucleotide starting from the back, just a hit. It works for me.

Yes, you are absolutely right. This is the best way to solve these questions ;)

raheel_memon 03-15-2010 02:04 PM

Its "B" .....

Seetal 03-17-2010 02:08 AM

yep yep B
 
definitely. thats what i did. cDNA, then:) find its hybrid and reverse it because the end result (even for primer design) must always be shown in the sense strand (5' to 3') fashion.

ely83 03-21-2010 06:53 PM

I think the correct one is answer B:

since they don't specify, you assume that the sequences are written in a 5'-3' direction. The hibridizing (binding) segment to that oligonucleotide should be complementary to it, thus it should be 3'-ATGCTAGTATA-5'. But since they write it on a 5'-3' direction, you have to reverse it. Thus it becomes 5'- ATATGATCGTA-3', answer B.

Does it make sense?

Quote:

Originally Posted by Farazdaq (Post 5555)
TACGATCATAT is an oligonucleotide probe used to construct a cDNA library to study the transcriptome of genetically modified mice.
Which of the following coding strands will correctly hybridize with the probe in question?

A- TACGATCATAT
B- ATATGATCGTA
C- AUGCUAGUAUA
D- GCATATACGCG
E- AUAUGAUCGUA


Seetal 03-22-2010 06:52 AM

yes ely83
 
Quote:

Originally Posted by ely83 (Post 6496)
I think the correct one is answer B:

since they don't specify, you assume that the sequences are written in a 5'-3' direction. The hibridizing (binding) segment to that oligonucleotide should be complementary to it, thus it should be 3'-ATGCTAGTATA-5'. But since they write it on a 5'-3' direction, you have to reverse it. Thus it becomes 5'- ATATGATCGTA-3', answer B.

Does it make sense?

yes ely. that's what i meant. reverse it!!:) awesome. we're at par.

dr_lizard 09-05-2011 04:22 PM

does using the template instead of coding changes the answer? :rolleyes:


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