Midfielder joins Bristol on loan.John-Joe will initially be with Rovers until January 29th.
Rovers are currently in the bottom two in League Two and John has initially been appointed until the end of the season with the aim of taking them away from trouble at the foot of the table.
The move west reunites him with former U's boss John Ward, who makes John-Joe one of his first signings for the club after his recent arrival at the Memorial Stadium.
John-Joe recently returned from injury and, after a couple of appearances from the U's substitutes' bench, he will look to get some regular first team action under his belt with Rovers.
U's midfielder John-Joe O'Toole has headed to Bristol Rovers on loan, joining the League Two side for a month.