May be involved in the regulation of aggregation. Activates tgrC1. Developmentally regulated; with a peak of expression at 16 hours corresponding to the finger stage of development. Cells are unable to sporulate when in pure population although they will sporulate when in chimerae with wild-type cells. Cells form loose aggregate before disaggregating. Cells aggregate and disperse repeatedly. After starvation, cells completely fail to stream and display cAMP relay defects. Fail to rotate. comC-/tgrC1-/tgrD1- triple mutants fail to form spores.