Protein Domain : Toxin SymE-like IPR014944

Type	Domain
Description	SymE (SOS-induced yjiW gene with similarity to MazE) is an SOS-induced toxin. It inhibits cell growth, decreases protein synthesis and increases RNA degradation. It may play a role in the recycling of RNAs damaged under SOS response-inducing conditions. Its translation is repressed by the antisense RNA SymR, which acts as an antitoxin [ , ].SymE belongs to type I toxin-antitoxin systems, but it does not show functional homology to other type I toxin proteins. Its function resembles that of type II toxins such as MazF, which can cleave mRNA independent of the ribosome. However, SymE has homology to the AbrB-fold superfamily proteins such as MazE, which act as transcriptional factors and antitoxins in various type II TA modules [ ]. It seems probable that SymE has evolved into an RNA cleavage protein with toxin-like properties from a transcription factor or antitoxin [].
Short Name	Toxin_SymE-like