The alternative splicing of the T-antigen gene of simian virus 40 (SV40) is regulated by the presence of splicing factor 2 (SF2), which is a(n) protein that contains two domains, an RNA-binding region and another domain with alternating serine and arginine amino acids.

Explanation:

Splicing is of two types: constitutive and alternative splicing

Alternative splicing produces different mRNA from the same pre-mRNA.

Splicing is a very tightly regulated process and involve various factors and enzyme. SR protein is a  serine /arginine-rich proteins, is a family of highly conserved splicing regulators that this is also involved in other steps like  in RNA biogenesis and expression. These SR proteins are necessary for viral RNA processing. SR protein contains two domains, i) an RNA-binding region and ii) another domain with alternating serine and arginine amino acids.

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