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  #1  
Old 02-26-2010
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DNA 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
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  #2  
Old 02-26-2010
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Default C

C IS the ans i guess
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  #3  
Old 02-26-2010
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Default It's not C

Quote:
Originally Posted by Aditya View Post
C IS the ans i guess
So contains uracil, DNA template strands do not contain Uracil
I think the answer is B
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  #4  
Old 02-26-2010
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Default ooops

yea a blunder, i made...havent read mol biochemistry yet..
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Old 03-05-2010
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Agreed - i think it's B too...
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Old 03-14-2010
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B, cDNA complementery & antiparallel. Match the nucleotide starting from the back, just a hit. It works for me.
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  #7  
Old 03-15-2010
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Wink Yes

Quote:
Originally Posted by bianca View Post
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
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Old 03-15-2010
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Its "B" .....
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  #9  
Old 03-17-2010
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Thumbs Up 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.
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Old 03-21-2010
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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 View Post
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
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  #11  
Old 03-22-2010
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Default yes ely83

Quote:
Originally Posted by ely83 View Post
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.
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  #12  
Old 09-05-2011
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does using the template instead of coding changes the answer?
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