In addition to the other rulemaking powers conferred upon the commissioner by this title, the commissioner is authorized and directed to adopt rules governing the issuance, offering and sale of investment certificates by industrial investment companies or thrift certificates by industrial banks and all operations of industrial investment companies and industrial banks in connection therewith, in order to protect the interests of the holders of the certificates, including, but not limited to, the maintenance of appropriate reserves.
T.C.A. § 45-5-606