WHAT??? Your transmitter is "Talking" and your PIC should be "Listening"; or receiving. In order for your PIC to receive/listen, your pin3 must be configured as a digital (ANSEL Register reads 0 for that pin) input (TRIS Register set to 1 for that pin). For you to have your PIC make that transmission line low, you have to clear the TRIS bit to make it an output, then use either the PORT or LAT Register to make the pin3 low.

WHAT DOES ANY OF THIS HAVE TO DO WITH RECEIVING A TRANSMISSION??!!?!?!??? What do you hope to accomplish??