Question

do G-protein-linked-receptors help in long distance signaling

Answer 1

I assume that by long distance signaling you mean a target cell that is far from the source of the ligand (the molecule that binds to the receptor). If that is the case, then yes, G-protein linked receptors are involved with long distance signaling.

G-proteins are used in many cellular pathways. An example of a "long distance" signal would be adrenaline receptors (both main types i believe, but definitely beta adrenergic receptors). Adrenaline is released from the adrenal gland and makes its way through the blood stream to the target tissues.