Explain why an mRNA transcribed from the template strand of the SIRT3 gene in normal stomach ( NS ) cells is translated to produce a SIRT3 protein of correct sequence, but if an mRNA were transcribed from the nontemplate strand of the SIRT3 gene in these cells, it would not produce a SIRT3 protein of correct sequence.

Explanation:

The double-stranded DNA molecule has the  potential to store genetic information in either strand, although in  most organisms only one strand is used to encode any particular gene.  

The template strand is the non-coding strand. The coding strand of DNA is the non-template (mRNA-like) strand (see attachment).

Thus, genetic  information is expressed by transcription of the non-coding (template) strand  of DNA, which produces an mRNA molecule that has the same sequence  as the coding strand of DNA. Therefore, if a mRNA is transcribed from the non-template strand, the genetic information will not be contained in that strand and it would not produce a correct protein.