With the approval of the comptroller, the board of regents of The University of Texas System may appoint one or more commercial banks, depository trust companies, or other entities to serve as a custodian or custodians of the permanent university fund’s securities with authority to hold the money realized from those securities pending completion of an investment transaction if the money held is reinvested within one business day of receipt in investments determined by the board of regents. Money not reinvested within one business day of receipt shall be deposited in the state treasury not later than the fifth day after the date of receipt.