Oct 10 (Reuters) - DeFi protocol Ethena announced on Thursday that it will invest its $46 million reserve fund in BlackRock and Securitize's tokenisation fund BUIDL, Mountain's USDM tokens, Superstate's USDM, and Sky (formerly known as Maker)'s new stable The agreed reserve fund will allocate about $18 million in BUIDL, $13 million in USDM, $8 million in USDM and $7 million in USTB, according to a Governance Forum post.