The phrase "a vital function in" is correct and usable in written English.
It can be used to describe an essential role or purpose that something serves within a particular context or system.
Example: "The heart plays a vital function in circulating blood throughout the body."
Alternatives: "an essential role in" or "a crucial part in".
The three main agencies – Experian, Equifax and CallCredit – perform a vital function in a world that lives on credit.
I saw that these people served a vital function in society, and yet were paid so little.
The results of this study indicate that GO has a vital function in catalyzing the photo-Fenton process.
Dr. Olson said he believed the majority of university-based cadaver programs were properly run and served a vital function in medical education.
It demanded the ban be overturned, because "the LMSS serves a vital function in the social, academic and philanthropic areas of medical student life".
Sleep has been assumed to be necessary for development and to be a vital function in mammals1,2 and other animals3,4.
Using documents from the management office, the companies verify proxy signatures -- a vital function, particularly in hotly contested elections in which abuse is possible.
Our findings indicate a vital function for MECP2 in maintaining active gene transcription in human neuronal cells.
Also, our previous work indicated that Ring1B knockout mice die early in gestation, with severe defects in the mesoderm and deregulated hox gene expression [28], suggesting a vital function for Ring1B in early embryo development.
This is a vital function of Sadness in the film: It guides Riley to recognize the changes she is going through and what she has lost, which sets the stage for her to develop new facets of her identity.
However, genes that are members of functionally redundant gene families, or genes that have a vital function and therefore result in lethal mutant phenotypes, are difficult to identify.
