Fig. 1.

Proteins encoded by mutated LHX3 genes display impaired gene activation properties. A. Schematic showing wild type (WT) and mutant LHX3 proteins: a, b = LHX3a- and LHX3b-specific amino terminal domains; L1, L2 = LIM domains; HD = homeodomain; C-AD = carboxyl activation domain. Black box = “missense” protein sequence resulting from frame shift. B. Expression vectors for wild type and mutant LHX3 proteins were transiently cotransfected into pituitary GHFT1 cells with a luciferase reporter gene under the control of the FSHβ promoter. Promoter activity was assayed by measuring luciferase activity 48 hr after transfection. Negative controls (Control) received equivalent amounts of empty expression vector plasmid. Activities are mean [light units/10 seconds/μg total protein] of triplicate assays ± S.E.M. A representative experiment of at least three experiments is depicted.