The phrase "an important actor" is correct and usable in written English.
It can be used to refer to someone or something that plays a significant role in a particular context, such as in politics, business, or a specific event.
Example: "In the recent negotiations, she emerged as an important actor in shaping the outcome."
Alternatives: "a key player" or "a significant participant."
These studies have shown that tryptase modulates the proliferation of these cells through the cleavage of protease-activated receptor-2 (PAR-2) and a subsequent increase in COX-2 expression, a finding adding further importance to the role of COX-2 as an important actor for myogenesis in situation of skeletal muscle repair.
Hezbollah is clearly an important actor in this situation.
But in some regions and for some types of extreme temperature events, shifts in atmospheric circulation are an important actor.
Until the 90s he was an important actor - he died in 2004 - and it's still a great song.
Higher education institutions (HEIs) are, as a sector, an important actor in society and their role in sustainability transition has been acknowledged.
If fraud and exuberance are the primary drivers of these new digital asset markets, and because investors have become reliant on the SEC, the regulators will be an important actor in making an efficient market.
The S.C.O. was initially ignored by Russia when it was set up a decade ago, but it has steadily developed into an increasingly important actor that has become a vehicle for China's push to develop Central Asia.
Since a growing number of evidences indicate that autophagy seems to be an increasingly important actor of cardiomyocyte remodelling, we also studied its implication in MMV compared to healthy mitral valves (HMV).
While using the methods of a classicist to increase our understanding of no as literary texts, she also demonstrates that the fifteenth-century treatises of Zeami--an important playwright, actor, critic, and teacher of no--offer fresh insight into Aeschylus' use of actors, language, and various elements of stage presentation.
The army remains the one institution that embodies national character in the country and would be a vitally important actor in any response to a natural disaster.
Mr. Obama called on Hamas to forswear violence and recognize Israel's right to exist, but Middle East experts said that his mention was an acknowledgment that Hamas might have become a more important actor than the Fatah Party, controlled by Mahmoud Abbas, the Palestinian president.
