How is the template strand for a particular gene determined?

The question is incomplete as it does not have the options which are:

-It is established by the promoter.

-It is the DNA strand that runs from the 3′ → 5′ direction

-It doesn't matter which strand is the template because they are complementary and will produce the same mRNA.

-It is the DNA strand that runs from the 5′ → 3′ direction.

-It is signaled by a polyadenylation signal sequence.

Answer:

-It is established by the promoter.

Explanation:

A promoter is a sequence of nucleotides about 1000 bp in the gene which contains the specific nucleotides in the sequence.

The promoter sequence contains the sequence for binding of the RNA polymerase, specific TATA nucleotides, and TSS or transcription start site.

It is the presence of this promoter which determines which strand will be the template strand and which will be the coding strand.

Since the transcription promoter is usually present on the strand which runs from 3' to 5' as RNA polymerase bind new nucleotide at 3'end of the growing chain, therefore, the strand with promoter sequence in that direction decides the fate of the DNA strands and transcription.