[Pioneer Transcription Factors in Normal Development and in Carcinogenesis]

Pioneer transcription factors constitute a heterogeneous group of regulatory proteins of animals, which, unlike other transcription factors, are able to recognize and bind target DNA sequences within closed chromatin. This binding can change the local chromatin structure and facilitate binding of other proteins, thus establishing competence for gene expression. The ability to bind silent genes in the closed environment makes the pioneer factors very useful in the processes leading to cardinal alteration of cell phenotype, such as differentiation in embryonic development or cell reprogramming. These proteins can remain bound to target sequences during mitotic division, and due to this probably take part in the maintenance of cellular memory. Apparently, pioneer transcription factors are active participants in carcinogenesis and maintenance of tumor cell phenotype, although their role in these processes needs additional research. It is reasonable to suppose that a further study will help to shed more light on the genetic processes in embryonic development, increase the efficiency of cell reprogramming and also develop new approaches to diagnostics and therapy of cancer diseases.