Abstract
Here we describe novel spherical structures that are induced by cold shock on the lampbrush chromosomes (LBCs) of Xenopus laevis oocytes. We call these structures cold bodies or C-bodies. C-bodies are distributed symmetrically on homologous LBCs, with a pattern similar to that of 5S rDNA. Neither active transcription nor translation is necessary for their formation. Similar protrusions occur on the edges of some nucleoli. Endogenous LBCs as well as those derived from injected sperm form C-bodies under cold shock conditions. The function of C-bodies is unknown.