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Full list of author information is available at the end of the articleIntroduction Glycogen synthase kinase-3 (GSK-3) is a ubiquitously expressed serine/threonine kinase, occurring in the two closely related isoforms GSK-3α and GSK-3β which share high homology in their kinase domains [1-3]. Originally, GSK-3 was discovered for its role in glucose metabolism by regulating glycogen synthase activity [3,4]. Over the years, interest in GSK-3 signalling has increased as it became apparent that this kinase regulates various physio-logical pathways involved a wide array of processes, in-cluding protein synthesis, cell differentiation, apoptosis and cell survival [5,6]. Currently, over fifty putative sub-strates have been identified including structural proteins, various intracellular signalling intermediates and tran-scription factors [6]. For instance, GSK-3 is critically in-volved as a negative regulator in β-catenin signalling and in the regulation of smad-dependent signalling [5,6]. Both these pathways are important in developmental processes and may be activated during pathological conditions in the lungs [7-10]