UASt sequences regulate expression of N in which a. the N-terminal EGF repeat containing part of the extracellular domain has been replaced by sequence encoding a signal peptide and Tag:LBD(FSHR) and b. the juxtamembrane NRR (negative regulatory region) has been replaced with the A2 domain of the Homo sapiens VWF gene (HGNC:12726), mutated to carry a I1628T amino acid substitution. The coding sequence is tagged with mCherry just upstream of the A2 domain and with Tag:V5 in the intracellular domain. A single FRT site is present in between the UASt and coding sequences.