Except as otherwise provided by this subtitle, in this subtitle, "state agency" means:
(1) a department, commission, board, office, or other agency in the executive branch of state government created by the state constitution or a state statute;
(2) the supreme court, the court of criminal appeals, a court of appeals, or the Texas Judicial Council; or
(3) a university system or an institution of higher education as defined by Section 61.003, Education Code, except a public junior college.