Spherulation-specific family 4. This protein is found in bacteria, archaea and eukaryotes. Proteins in this family are typically between 250 and 398 amino acids in length. There is a conserved NPG sequence motif and there are two completely conserved G residues that may be functionally important. Starvation will often induce spherulation - the production of spores - and this process may involve DNA-methylation. Changes in the methylation of spherulin4 are associated with the formation of spherules, but these changes are probably transient. Methylation of the gene accompanies its transcriptional activation, and spherulin4 mRNA is only detectable in late spherulating cultures and mature spherules. It is a spherulation-specific protein.