Quantitative human requirement for proteins and individual amino acids.

I'll give you an example: we know that the O blood type individual has a much higher requirement for protein than any other blood type.

The requirement for protein synthesis in Wnt signaling means that we cannot use cycloheximide sensitivity as a criterion to discriminate between primary and secondary targets.

These factors are ubiquitously expressed and it is proposed that defects in a ubiquitous factor (a protein expressed everywhere) should only cause disease in the retina because the retinal photoreceptor cells have a far greater requirement for protein processing (rhodopsin) than any other cell type.