NIK1 — Aspergillus fumigatus

Summary

AFU2G03560, symbol NIK1 (also known as AfNIK1, AfOS-1, or NIKA) in Aspergillus fumigatus on chromosome 2, encodes a histidine kinase with osmosensor, peroxide sensor, and histidine phosphotransfer kinase activities. This protein has phosphorelay sensor kinase and response regulator activity, and binds ATP. NIK1 is associated with the cellular HOG response, osmolarity sensing via a two-component system, MAPK cascade, and histidyl-aspartyl phosphorelay. It is linked to regulation of conidium formation, ascospore formation, filamentous growth, single-species biofilm formation on inanimate substrates, and fungal-type cell wall biogenesis. The gene is also associated with downregulation of phagocytosis and calcium-independent cell-cell adhesion, as well as cellular responses to cation stress, farnesol, and reactive oxygen species. NIK1 localizes to the plasma membrane, cytoplasm, cell tip, and cell division site. Studies of related genes in other species link the family to oxidative stress response and virulence.