Subspace-constrained reconstruction is a powerful technique to accelerate dynamic MRI. However, its performance is relatively limited for applications where a robust temporal model is not available. This work proposes to estimate temporal basis from undersampled dynamic golden-angle radial data without the need of a model or additional navigators, and to apply the estimated temporal basis for subspace-constrained reconstruction of undersampled dynamic images. The reconstruction algorithm also enforces an additional low-rank constraint on the resulting low dimensional dynamic images in the subspace. The proposed self-estimated subspace-constrained reconstruction technique was demonstrated for DCE-MRI of the prostate.