1.The transfer nce c0mplete by way of execution and registration of deed of conveyance cannot be cancelled by the transferor anymore.
2.In your case if you have already gifted your share through registered deed of gift to your brother then I regret ypu can not claim it back anymore.
3. You can get your share back only of your brother wants for which he can similarly gift that gifted part to you by way of deed of gift.
So act accordingly.