Maf, part of the large Maf transcription factor family, has been investigated for its role in various biological processes, especially in lens development [1].

In a study on mouse lens development, MafA/L-Maf and MafB were expressed in lens epithelial and fibre cells at E12.5 but diminished by E18.5. However, the lenses of mafA-deficient, mafB-deficient, and mafA::mafB double-deficient mice developed normally. In c-maf-deficient mice, the expression patterns of MafA and MafB differed from wild-type mice, yet the expression of crystallin genes was unchanged in mafA -, mafB -, and mafA::mafB double-deficient lenses. These results suggest that c-Maf alone is essential for lens development, while MafA/L-Maf and MafB are dispensable in mice [1].

In conclusion, while MafA/L-Maf and MafB may not be essential for mouse lens development, the study of their functions, especially through gene-knockout mouse models, provides insights into the complex regulatory mechanisms of tissue development. Understanding the roles of Maf genes can contribute to the knowledge of normal development and potentially related developmental disorders [1].