Cell-type-specific and developmental regulation of heterogeneous nuclear ribonucleoprotein K mRNA in the rat nervous system

• Published in: Gene Expression Patterns 2006-08, Vol.6 (6), p.596-606
• Main Authors: Blanchette, Adam R., Fuentes Medel, Yuly F., Gardner, Paul D.
• Format: Article
• Language: English
• Subjects: Animals; Central Nervous System - embryology; Central Nervous System - metabolism; Development; Female; Gene expression; Heterogeneous nuclear ribonucleoprotein K; Heterogeneous-Nuclear Ribonucleoprotein K - genetics; Heterogeneous-Nuclear Ribonucleoprotein K - metabolism; Hippocampus - embryology; Hippocampus - metabolism; Immunohistochemistry; Nervous system; Organ Specificity; Peripheral Nervous System - embryology; Peripheral Nervous System - metabolism; Rats; Rats, Sprague-Dawley; Retina - embryology; Retina - metabolism; RNA, Messenger - analysis
• ISSN: 1567-133X; 1872-7298
• DOI: 10.1016/j.modgep.2005.11.008

Heterogeneous nuclear ribonucleoprotein K (hnRNP K) was originally identified as being part of the hnRNP particle. hnRNP K has subsequently been shown to be involved in a number of fundamental biological processes such as RNA transport and processing as well as transcription and translation. In addition, hnRNP K is an integral player in a variety of intracellular signal transduction pathways. Not surprisingly given this broad array of cellular functions, hnRNP K is a highly interactive protein binding directly to both single- and double-stranded nucleic acids as well as numerous signaling proteins. Interestingly, earlier studies demonstrated that hnRNP K protein is not ubiquitously expressed and does not exist in a fixed stoichiometry with other hnRNP proteins. We have extended this earlier work and report here the spatially- and developmentally-regulated expression of hnRNP K mRNA during development of the rat nervous system. In the central nervous system, hnRNP K mRNA expression gradually decreases during development until it is restricted to a very limited number of structures including most notably the hippocampus and the retina. Immunohistochemical data indicate that hnRNP K protein expression closely parallels hnRNP K mRNA expression. In contrast to the central nervous system, hnRNP K in the peripheral nervous system remains high throughout embryonic development with dramatic expression in several peripheral ganglia.