TY - JOUR A1 - Tsukaya, Hirokazu A1 - Byrne, Mary E. A1 - Horiguchi, Gorou A1 - Sugiyama, Munetaka A1 - Van Lijsebettens, Mieke A1 - Lenhard, Michael T1 - How do 'housekeeping' genes control organogenesis?-unexpected new findings on the role of housekeeping genes in cell and organ differentiation JF - Journal of plant research N2 - In recent years, an increasing number of mutations in what would appear to be 'housekeeping genes' have been identified as having unexpectedly specific defects in multicellular organogenesis. This is also the case for organogenesis in seed plants. Although it is not surprising that loss-of-function mutations in 'housekeeping' genes result in lethality or growth retardation, it is surprising when (1) the mutant phenotype results from the loss of function of a 'housekeeping' gene and (2) the mutant phenotype is specific. In this review, by defining housekeeping genes as those encoding proteins that work in basic metabolic and cellular functions, we discuss unexpected links between housekeeping genes and specific developmental processes. In a surprising number of cases housekeeping genes coding for enzymes or proteins with functions in basic cellular processes such as transcription, post-transcriptional modification, and translation affect plant development. KW - Development KW - Housekeeping genes KW - Post-transcriptional modification KW - RNAPII KW - Pre-mRNA splicing KW - Ribosome KW - 3 '-end processing KW - Transcription KW - Translation Y1 - 2013 U6 - https://doi.org/10.1007/s10265-012-0518-2 SN - 0918-9440 VL - 126 IS - 1 SP - 3 EP - 15 PB - Springer CY - Tokyo ER - TY - JOUR A1 - Junemann, Alexander A1 - Winterhoff, Moritz A1 - Nordholz, Benjamin A1 - Rottner, Klemens A1 - Eichinger, Ludwig A1 - Gräf, Ralph A1 - Faix, Jan T1 - ForC lacks canonical formin activity but bundles actin filaments and is required for multicellular development of Dictyostelium cells JF - European journal of cell biology N2 - Diaphanous-related formins (DRFs) drive the nucleation and elongation of linear actin filaments downstream of Rho GTPase signalling pathways. Dictyostelium formin C (ForC) resembles a DRF, except that it lacks a genuine formin homology domain 1 (FH1), raising the questions whether or not ForC can nucleate and elongate actin filaments. We found that a recombinant ForC-FH2 fragment does not nucleate actin polymerization, but moderately decreases the rate of spontaneous actin assembly and disassembly, although the barbed-end elongation rate in the presence of the formin was not markedly changed. However, the protein bound to and crosslinked actin filaments into loose bundles of mixed polarity. Furthermore, ForC is an important regulator of morphogenesis since ForC-null cells are severely impaired in development resulting in the formation of aberrant fruiting bodies. Immunoblotting revealed that ForC is absent during growth, but becomes detectable at the onset of early aggregation when cells chemotactically stream together to form a multicellular organism, and peaks around the culmination stage. Fluorescence microscopy of cells ectopically expressing a GFP-tagged, N-terminal ForC fragment showed its prominent accumulation in the leading edge, suggesting that ForC may play a role in cell migration. In agreement with its expression profile, no defects were observed in random migration of vegetative mutant cells. Notably, chemotaxis of starved cells towards a source of cAMP was severely impaired as opposed to control. This was, however, largely due to a marked developmental delay of the mutant, as evidenced by the expression profile of the early developmental marker csA. In line with this, chemotaxis was almost restored to wild type levels after prolonged starvation. Finally, we observed a complete failure of phototaxis due to abolished slug formation and a massive reduction of spores consistent with forC promoter-driven expression of beta-galactosidase in prespore cells. Together, these findings demonstrate ForC to be critically involved in signalling of the cytoskeleton during various stages of development. KW - Actin bundles KW - Cell migration KW - Chemotaxis KW - Development KW - Dictyostelium KW - Formin KW - Morphogenesis KW - Phototaxis KW - Spore formation Y1 - 2013 U6 - https://doi.org/10.1016/j.ejcb.2013.07.001 SN - 0171-9335 VL - 92 IS - 6-7 SP - 201 EP - 212 PB - Elsevier CY - Jena ER -