Defensin Alpha 4, Corticostatin (DEFa4)

Defensins are a family of microbicidal and cytotoxic peptides thought to be involved in host defense. They are abundant in the granules of neutrophils and also found in the epithelia of mucosal surfaces such as those of the intestine. This gene differs from other genes of this family by an extra 83-base segment that is apparently the result of a recent duplication within the coding region.DEFa4 is found in the neutrophils; it exhibits corticostatic activity and inhibits corticotropin stimulated corticosterone production.The nucleotide sequence shares about 72% identity with the cDNA encoding defensin HP-1 , but differed from it and from other genes of this family by an extra 83-base segment. This extra segment was not adjacent to an intron and was apparently the result of a recent duplication within the coding region corresponding to most of the mature HP-4 peptide.