●Checkpoint signalling: focusing on 53BP1. Abraham, R. T. Nature Cell Biology December (2002). News and Views article discussing three recent reports that indicate important roles for the p53-interacting protein — 53BP1 — in the S and G2 checkpoints after ionizing radiation exposure.

●The many faces of the retinoblastoma tumour suppressor in development and cancer. Classon, M. & Harlow, E. Nature Reviews Cancer December (2002).

●Regulation of transcription factors by neuronal activity. West, A. E., Griffith, E. C. & Greenberg, M. E. Nature Reviews Neuroscience December (2002).

●Dual-specificity phosphatases as targets for antineoplastic agents. Lyon, M. A., Ducruet, A. P., Wipf, P. & Lazo, J. S. Nature Reviews Drug Discovery December (2002).

●Blocking NO synthesis: how, where and why? Vallance, P. & Leiper, J. Nature Reviews Drug Discovery December (2002).

●Enzyme replacement and enhancement therapies: lessons from lysosomal disorders. Desnick, R. J. & Schuchman, E. H. Nature Reviews Genetics December (2002).

●SV40 and human tumours: myth, association or causality? Gazdar, A. F., Butel, J. S. & Carbone, M. Nature Reviews Cancer December (2002).

●Pathogenesis of Parkinson's disease: dopamine, vesicles and α-synuclein. Lotharius, J. & Brundin, P. Nature Reviews Neuroscience December (2002).

●The stem-cell niche theory: lessons from flies. Lin, H. Nature Reviews Genetics December (2002).

●Nature Reviews Immunology focus on decision making in the immune system. Nature Reviews Immunology December (2002). A special issue examining how signals that are specific to the immune system — for example, cytokines and antigens — influence cell fate at the biochemical, transcriptional and epigenetic levels.

●Lymphoid malignancies: the dark side of B-cell differentiation. Shaffer, A. L., Rosenwald, A. & Staudt, L. M.

●Chromatin and CD4, CD8A and CD8B gene expression during thymic differentiation. Kioussis, D. & Ellmeier, W.

●Regulation of B-cell fate by antigen receptor signals. Niiro, H. & Clark, E. A.