Perc

PerC is a gene name used in microbiology, most notably as a transcriptional regulator in Salmonella enterica and related Enterobacteriaceae. The PerC protein participates in the regulatory network that controls expression of the Salmonella pathogenicity island 1 (SPI-1) type III secretion system, which is essential for invasion of host cells.

In Salmonella SPI-1 regulation, PerC positively influences the transcription of hilA, a key master regulator of invasion genes. Through HilA, PerC indirectly activates a broad set of SPI-1 invasion genes, including those encoding the secretion apparatus and effector proteins. PerC acts in concert with other regulators such as HilD, HilC, and RtsA, forming a complex regulatory cascade that integrates environmental signals to modulate virulence gene expression.

Genetic context and significance: PerC is commonly located within SPI-1 in many Salmonella strains and related species. Experimental alterations of perC can alter SPI-1 expression and invasion efficiency, making PerC a useful model for studying regulatory networks of virulence. The PerC regulatory module is frequently cited in discussions of hierarchical regulation of the SPI-1 regulon, alongside HilD, HilC, RtsA, and HilA.

See also: Salmonella pathogenesis island 1 (SPI-1), HilA, HilD, HilC, RtsA. Note that PerC is primarily encountered in bacterial genetics and is not a broadly used acronym outside this context.