Between which phosphate groups is the linkage that connects the GTP molecule to the RNA chain in the 5' cap?

The correct choice refers to the linkage between the alpha and beta phosphate groups of the guanosine triphosphate (GTP) molecule and the RNA chain in the 5' cap. The 5' cap structure involves the attachment of the first guanine nucleotide of the RNA to the 5' end of the RNA chain through a 5'-5' triphosphate bridge. This bridge is specifically formed between the beta phosphate group of GTP and the alpha phosphate group of the first nucleotide in the RNA molecule. The significance of this particular linkage is that it forms a stable structure that protects the RNA from degradation by exonucleases and plays a crucial role in the initiation of translation and splicing.

The other options do not describe the correct phosphate groups involved in this specific interaction. The beta-gamma and alpha-alpha options do not represent the actual connection made for the GTP molecule to the RNA chain at the 5' cap. Understanding this specific linkage is key to grasping the biochemical functionality of the RNA cap structure in mRNA stability and translation efficiency.