(TMZ) -- Alexis Arquette died a year ago on September 11, and her brother, David Arquette, still gets choked up talking about keeping her memory alive.

TMZ got David Monday night at Bootsy Bellows, where he and his fam were holding a memorial for Alexis ... who died of a heart attack and battled HIV for years.

He talked about launching the Alexis Project to support LGBT communities in L.A. He also told TMZ what he thinks Alexis' legacy will be.

Emotional moment, but Dave did laugh when we asked how Alexis would have wanted the party to go.

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