Figure 1.

A model for the buffering role of Hsp90 in canalization. Hsp90 conceals cryptic genetic mutations. (a) When Hsp90 is normal, underlying genetic variation (gray peaks) is hidden and genetic signal inputs (black peaks) are outputted normally, resulting in a phenotype that varies within normal limits. (b) When Hsp90 is impaired, hidden genetic variation is revealed, resulting in altered genetic signal inputs (black peaks) that are abnormally outputted. These altered outputs may lead to an abnormal phenotypic variation.