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  #1  
Old 11-08-2012
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Question immuno 2

a researcher is going to study regarding HIV infection.He makes a substance X and then he inserts the substance xto the transgenic mice.mice starts producing large amounts of CTLs .the substance he injected particularly acts on.
a)tat gene
b)CXCR4
d)POL gene
e)nef gene
f)CCR5
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  #2  
Old 11-08-2012
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i think it's E) nef gene........but not that sure...went with it coz nef gene decreases MHC1 expression on infected cells

thanks for the question...
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  #3  
Old 11-08-2012
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I think CXCR4 since it's found in T cells................
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  #4  
Old 11-08-2012
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Correct Answer e

normally nef gene decreases expression of MHC 1.so substance x acts on nef gene to decrease its secretion>>>>>increase MHC 1>>>>>increase in CTLS.........
I like this concept ....
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  #5  
Old 11-08-2012
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Quote:
Originally Posted by rupesh View Post
normally nef gene decreases expression of MHC 1.so substance x acts on nef gene to decrease its secretion>>>>>increase MHC 1>>>>>increase in CTLS.........
I like this concept ....
thanks for the question...

but i gotta doubt..i really wanna know how substance x decrease nef gene secretion(i mean is it presented in the question..?)............and do really such kinda substance exist..?...pls correct me..

thanks
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  #6  
Old 11-09-2012
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Quote:
Originally Posted by venky2600 View Post
thanks for the question...

but i gotta doubt..i really wanna know how substance x decrease nef gene secretion(i mean is it presented in the question..?)............and do really such kinda substance exist..?...pls correct me..

thanks
i just have asked in the last line of the question where actually the drugs works....and rest of the options does not increases CTLS .....so we have to assume that.....
thanks....
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  #7  
Old 11-09-2012
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Quote:
Originally Posted by rupesh View Post
normally nef gene decreases expression of MHC 1.so substance x acts on nef gene to decrease its secretion>>>>>increase MHC 1>>>>>increase in CTLS.........
I like this concept ....
VOILA..
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  #8  
Old 11-09-2012
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Quote:
Originally Posted by rupesh View Post
a researcher is going to study regarding HIV infection.He makes a substance X and then he inserts the substance xto the transgenic mice.mice starts producing large amounts of CTLs .the substance he injected particularly acts on.??
a)tat gene
b)CXCR4
d)POL gene
e)nef gene
f)CCR5
I will frame the same q in different way,i hope u wont mind,(just to refresh the concepts)
a researcher is going to study regarding HIV infection.He makes a substance X and then he inserts the substance xto the transgenic mice.mice shows decresed transcription of all HIV genes.The substance injected particularly acts on:

a)tat gene
b)CXCR4
d)POL gene
e)nef gene
f)CCR5
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  #9  
Old 11-09-2012
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Quote:
Originally Posted by trupti View Post
I will frame the same q in different way,i hope u wont mind,(just to refresh the concepts)
a researcher is going to study regarding HIV infection.He makes a substance X and then he inserts the substance xto the transgenic mice.mice shows decresed transcription of all HIV genes.The substance injected particularly acts on:

a)tat gene
b)CXCR4
d)POL gene
e)nef gene
f)CCR5
i'll go with A) tat gene...........

thanks
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  #10  
Old 11-09-2012
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Originally Posted by venky2600 View Post
i'll go with A) tat gene...........

thanks
yup!..trans activator of transcription(tat)-mutation /inactivation:reduces transcription of HIV genes.Tat antagonist have been studied for rx of HIV.
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