The tax rules provide that you should make a reasonable allocation of the expenses. That applies to depreciation as well as the MFs and taxes.
Because the square footage, fair market value and rental value of the studio are all likely to be less that one half of the total, I believe something in the range of 25%-35% of the total would be appropriate, but it's your call.
Also, if you have used the unit for personal use (occupancy, exchange, gift to a friend or relative, etc.) in any prior year, depreciation should be calculated based on resale value or your purchase price, whichever is lower.