Contributes to surface hydrophobicity, which is important for processes such as association of hyphae in reproductive structures, dispersal of aerial spores and adhesion of pathogens to host structures. Important for the formation of hydrophobic rodlet layers of asexually-produced spores. Accumulates during conidiation but not during germination. Expression is controlled by blue light and by a circadian clock. Also induced by glucose, nitrogen and carbon starvation. Belongs to the fungal hydrophobin family.