The State Treasurer is the treasurer of the Disability Fund and shall have the custody of all money belonging to the Disability Fund and not otherwise held, deposited or invested under this part. The official bond of the State Treasurer shall cover the faithful performance of his or her duties as treasurer of the Disability Fund. The State Treasurer shall invest or otherwise deal with the Disability Fund under the supervision of the director. The State Treasurer may, pursuant to Section 16470 of the Government Code, file with the Pooled Money Investment Board a notice of election that investment of surplus money in the Disability Fund shall come under the provisions of the Surplus Money Investment Fund, and may revoke such election pursuant to Section 16470 of the Government Code. As of the effective date of any election with respect to the Disability Fund filed pursuant to Section 16470 of the Government Code, the State Treasurer shall transfer the surplus money in the Disability Fund to the Surplus Money Investment Fund, and may transfer all or any portion of the investments held by the Disability Fund at the date of such election, from the Disability Fund to the Surplus Money Investment Fund. As of the effective date of the revocation of any such election, the State Treasurer shall transfer from the Surplus Money Investment Fund to the Disability Fund the surplus money and earnings attributable to the Disability Fund.