Compositions and methods for regulating endogenous inhibitor of ATP synthase, including treatment for diabetes

A method for identifying an agent that alters mitochondrial ATP production, comprising:

• contacting, in the absence and presence of a candidate agent, an isolated IF1 polypeptide and an isolated mitochondrial ATP synthase, wherein the ATP synthase is capable of ATP synthesis, under conditions and for a time sufficient for ATP production to occur;
• and
• comparing a level of ATP production by the ATP synthase in the presence of the candidate agent to a level of ATP production in the absence of the candidate agent, and therefrom identifying an agent that alters mitochondrial ATP production.

A method of treating diabetes comprising administering to a patient in need thereof an effective amount of a compound that (a) increases the synthesis of mitochondrial ATP in cells, (b) decreases the hydrolosis of mitochondrial ATP in cells, or (c) does both (a) and (b).

A method of identifying an agent useful for treating diabetes, comprising comparing (i) a level of ATP in a biological sample comprising at least one mitochondrion before contacting the sample with a candidate agent, to (ii) the level of ATP in the sample after contacting the sample with the candidate agent, wherein an increased level of ATP indicates the agent is useful for treating diabetes.

A fusion protein comprising a polyhistidine tag set forth in SEQ ID NO:1 fused to an IF1 comprising any one of the amino acid sequences selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:12, 13, 29, 63, 64, 65, 66 and 67.

A fusion protein comprising (i) a polyhistidine tag set forth in SEQ ID NO:1, which is fused to (ii) a cellular transport sequence comprising a tat sequence comprising any one amino acid sequence selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:

• 10, 11 and 27, which is fused to (iii) a mitochondrial targeting sequence comprising an amino acid sequence set forth in SEQ ID NO:14, which is fused to (iv) an IF1 comprising any one amino acid sequence selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:12, 13, 29, 63, 64, 65, 66 and 67.

A fusion protein comprising (i) a polyhistidine tag set forth in SEQ ID NO:1, which is fused to (ii) a cellular transport sequence comprising a tat sequence comprising any one amino acid sequence selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:

• 10, 11 and 27, which is fused to (iii) an IF1 comprising any one amino acid sequence selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:12, 13, 29, 63, 64, 65, 66 and 67.

A fusion protein comprising (i) a polyhistidine tag set forth in SEQ ID NO:1, fused to (ii) a cellular transport sequence comprising a tat sequence comprising any one amino acid sequence selected from the group consisting of the amino acid sequences set forth in SEQ ID NOS:

• 10, 11, and 27.

A fusion protein comprising (i) a polyhistidine tag set forth in SEQ ID NO:

• 1, fused to (ii) a cellular transport sequence comprising a tat sequence comprising an amino acid sequence set forth in SEQ ID NO:
• 10, which is fused to (iii) an IF1 polypeptide comprising an amino acid sequence set forth in SEQ ID NO:29.