The charter of any institution of higher education, if issued by the Regents or by special act of the Legislature, which provides that admission to the institution shall be limited on the basis of sex shall, after approval by the commissioner of a plan for the admission of students of the opposite sex, including facilities, staff and program, and upon the filing with the Board of Regents of a resolution duly adopted upon the affirmative vote of no fewer than three-fourths of the whole number of trustees, deleting such limitation, be deemed to be amended accordingly.