Transformation of SP14NM protein into yeast induces [PSI+] only after fiber formation. The [PSI+] phenotype was assayed by color on YPD, growth on SD-ADE and curability (not shown). Control protein transformations show that protein harvested from either strong or weak [PSI+] cells transformed in to [psi-] cells induces the corresponding prion phenotype while protein harvested from [psi-] cells does not induce the prion state. Soluble SP14NM protein (SP14NMsol) does not induce the [PSI+] prion phenotype prior to fiber formation. SP14NM protein was able to induce the [PSI+] prion phenotype after fiber formation either at 4°C (SP14NM4, strong strain) or 25°C (SP14NM25, weak strain).
Kalastavadi and True BMC Biochemistry 2008 9:7 doi:10.1186/1471-2091-9-7