"function as a guardian" is correct and usable in written English.
You could use this phrase to describe someone who is responsible for taking care of and protecting someone or something. For example, "The teacher functions as a guardian for the safety of the students."
You may never need the person to function as a guardian, but it's best to make contingency arrangements while you can.
In an elegant paper published in the July 12 issue of Cancer Cell, Girardini and colleagues show how Pin1-mediated prolylisomerization, a regulatory mechanism intended by evolution to support p53's function as a guardian of the genome, can go haywire and accelerate malignant transformation when p53 carries a dominant-negative mutation.
The brothers' first effort, William K. Howard's "Johnny Come Lately," unveiled a sprightly, whimsical Cagney, who functioned as a guardian angel to an embattled small-town newspaper publisher, played as a sweet little old lady by Grace George.
In steroidogenic cells, SF-1 functions as a centrosomal guardian to maintain centrosome homeostasis.
Importantly, we reveal novel findings on the mechanism of threshold activation of p53 pulsatile and oscillatory dynamics that are important for its physiological function as the guardian of the genome.
Specifically we have presented evidence to suggest that while WT p53 might primarily function as the "guardian of the genome" (inducing cells to undergo apoptosis or cell cycle arrest under stress), the WT p53 gene sequence is evolutionarily maintained such that it is susceptible to inactivating mutations and consequent cell survival (with the untoward result of tumorigenesis).
Last year, the company said that it would invest $1 billion in a Silicon Valley-based research effort to focus on cars that will function as "guardian angels," saving human drivers from errors, rather than replacing them.
Two years ago, it formally renounced its "dual function" as guardian of political probity as well as of national security.
He obtained $4,400 worth of work as a guardian this year.
The man asks whether he could "sign off as a guardian," and the receptionist explains that the clinic does not ask for a guardian's signature.
The attitudinal lexis and the lexical metaphor construct this newspaper as a guardian of Australia.
