Krüppel-like factors (KLFs) are evolutionarily conserved zinc finger transcription factors that play a role in cell differentiation, proliferation, and pluripotency. KLF4 has specifically been tied to many diverse cellular processes, including self-renewal, apoptosis, and the correct development of the barrier function of skin. KLF4 can act as both an activator and a repressor, with these functions often being initiated during embryonic development. Not surprisingly, KLF4 is highly expressed in the skin and gut, and aids in kidney and skeletal development. Mutations in KLF4 have led to metabolic disorders, cardiovascular disease and many various cancers. In fact, KLF4 has been as shown through research to have the ability to reprogram adult fibroblasts into induced pluripotent stem cells, and the reprogramming of cancer cells with pluripotency factors has been recently proposed as a potential cancer therapy.
KLF4 was detected in immersion fixed D3 mouse embryonic stem cell line using Mouse KLF4 Antigen Affinity-purified Polyclonal Antibody (Catalog # AF3158) at 10 µg/mL for 3 hours at room temperature. Cells were stained using the NorthernLights™ 557-conjugated Anti-Goat IgG Secondary Antibody (red; Catalog # NL001) and counterstained with DAPI (blue). View our protocol for Fluorescent ICC Staining of Cells on Coverslips.
To first carve out the process of KLF4 activation, Kim et al used a KLF4 antibody and ERK1 and ERK2 antibodies to show that binding of ERK1 or ERK2 at the activation domain of Klf4 directly phosphorylates KLF4 at Ser123. This phosphorylation suppresses Klf4 activity, which in turn induces embryonic stem cell differentiation. On the flip side, when KLF4 phosphorylation is repressed, KLF4 activity is increased and mouse embryonic stem cell differentiation is suppressed. Next, Hawkins et al took a closer look at KLF4 post activation to investigate how it can regulate pluripotency and cell differentiation. Their group used a KLF4 antibody to show that in mouse embryonic stem cells (mESCs), a loss in E-Cadherin and N-Cadherin resulted in down regulation of production of KLF4. In the end, their data suggested that N-Cadherin and E-Cadherin were responsible for the regulation of STAT3, KLF4 and Nanog and in turn control (at some level) mESC pluripotentcy. Tai et al took a closer look at embryonic stem cell pluripotency, but this time their group focused on GBX2 as a reprogrammer of pluripotentcy. In order to survey this proteins involvement, they used a KLF4 antibody in immunocytochemistry to show that when GBX2 is overexpressed, KLF4 activity and subsequent mESC renewal is suppressed. This experiment helped to establish the link between GBX2 and mESC activity, which was very important for the remainder of their study. Furthermore, Letourneau et al used a KLF4 antibody to show that HSA single minded encoded 2 (Sim2) is a master transcription factor and involved in key neurological and developmental processes. Through genetic mapping and subsequent co-IP studies, Letourneau’s group was able to establish KLF4 as an important master transcription factor in embryonic stem cells as well.
Overall, it is clear that KLF4 has been established as a contributor to skin cell barrier function, kidney and skeletal development, and many cancers. However, through the mentioned research, it is also clear that KLF4 has a distinctive and strong role in development, specifically when it comes to studies in mouse embryonic stem cells.
Novus Biologicals offers KLF4 reagents for your research needs including:
- PMID: 22307056
- PMID: 22696497
- PMID: 23345404
- PMID: 25955728