Why does knocking out NACHO, but not RIC3, completely block expression of α7 nicotinic receptors in Mouse brain?

Anish Deshpande, Remitha M. Vinayakamoorthy, Brijesh K. Garg, Jaya Prakash Thummapudi, Gauri Oza, Ketaki Adhikari, Aayush Agarwal, Parnika Dalvi, Swetha Iyer, Sarulatha Thulasi Raman, Vijay Ramesh, Akshitha Rameshbabu, Alexandra Rezvaya, Sneha Sukumaran, Sweta Swaminathan, Bhargav Tilak, Zhiyuan Wang, Phu V. Tran, Ralph H. Loring