The gender roles play an important part of the theme of much ado about nothing. At the very start of the play we hear, ""You must not, sir, mistake my niece. There is a kind of merry war betwixt Signior Benedick and her: they never met but there's a skirmish of wit between them" (I.i.61-64).
It is a duel between Beatrice and Benedick, and it plays out during the whole play. The gender roles are pretty stereotypical; the woman are supposed to be submissive to the men. Their honor depends on their relationship with men. Woman's intuation (as evidenced by Beatrice's defense of Hero) is the most important and respected thing. The males are are bound together by honor and rank.
Of course, since this is much ado about nothing, all of the gender roles are confused and poses. The characters to not know this, but the audience does.