Usage patterns
〈組織〉の一翼を成すto form one part of (an organization, movement, field, etc.)
This institute forms one part of the country's defense system.
一翼を占めるto hold/occupy a share or part (of a larger effort)
She is an important person who holds a key part in the project.
Expressions
一翼を担うplay a part; take a share; shoulder a portion of responsibility