Mitogen-inducible-gene-6 is an endogenous inhibitor of HGF/Met-induced cell migration and neurite growth

Hepatocyte Growth Factor (HGF) is a pleiotropic factor acting on cells expressing the Met receptor tyrosine kinase. HGF/Met signaling has been described in detail and it is known to control cell migration, growth and differentiation in several embryonic organs and to be implicated in human cancer. Conversely, little is known about the transcriptional targets that lead to Met-mediated biological functions. Also, little is known about the physiological mechanisms that attenuate Met signaling. This work provides the results of a screen for genes transcriptionally regulated by Met in several cell lines and addresses the functions of the highly inducible gene Mig6 (Mitogen-inducible-gene6, also called Gene 33 and RALT). By the use of Met loss of function mutant mice Met is shown to be the major inducer of mig6 in hepatocytes and lungs of E13.5 embryos. Mig6 is shown in turn to negatively regulate HGF/Met-induced cell migration. The effect is observed by Mig6 overexpression and reversed by Mig6 siRNA knock down experiments indicating that endogenous Mig6 is part of a mechanism that inhibits Met signaling. Mig6 functions in cells of hepatic origin and in neurons suggesting a role for Mig6 in different cell lineages. Mechanistically, Mig6 requires an intact Cdc42/Rho interactive binding (CRIB) domain to exert its inhibitory action suggesting that Mig6 acts at least in part distally from Met possibly by sequestering Rho-like GTPases. Because Mig6 is also induced by HGF stimulation, this work provides evidence that Mig6 is part of a negative feedback loop that attenuates Met functions in different contexts and cell types

Mitogen-inducible gene 6 is an endogenous inhibitor of HGF/Met-induced cell migration and neurite growth

Hepatocyte growth factor (HGF)/Met signaling controls cell migration, growth and differentiation in several embryonic organs and is implicated in human cancer. The physiologic mechanisms that attenuate Met signaling are not well understood. Here we report a mechanism by which mitogen-inducible gene 6 (Mig6; also called Gene 33 and receptor-associated late transducer) negatively regulates HGF/Met-induced cell migration. The effect is observed by Mig6 overexpression and is reversed by Mig6 small interfering RNA knock-down experiments; this indicates that endogenous Mig6 is part of a mechanism that inhibits Met signaling. Mig6 functions in cells of hepatic origin and in neurons, which suggests a role for Mig6 in different cell lineages. Mechanistically, Mig6 requires an intact Cdc42/Rac interactive binding site to exert its inhibitory action, which suggests that Mig6 acts, at least in part, distally from Met, possibly by inhibiting Rho-like GTPases. Because Mig6 also is induced by HGF stimulation, our results suggest that Mig6 is part of a negative feedback loop that attenuates Met functions in different contexts and cell types

Identification and rejection of pile-up jets at high pseudorapidity with the ATLAS detector

The rejection of forward jets originating from additional proton–proton interactions (pile-up) is crucial for a variety of physics analyses at the LHC, including Standard Model measurements and searches for physics beyond the Standard Model. The identification of such jets is challenging due to the lack of track and vertex information in the pseudorapidity range |η| > 2.5. This paper presents a novel strategy for forward pile-up jet tagging that exploits jet shapes and topological jet correlations in pile-up interactions. Measurements of the per-jet tagging efficiency are presented using a data set of 3.2 fb−1 of proton–proton collisions at a centre-of-mass energy of 13 TeV collected with the ATLAS detector. The fraction of pile-up jets rejected in the range 2.5 < |η| < 4.5 is estimated in simulated events with an average of 22 interactions per bunch-crossing. It increases with jet transverse momentum and, for jets with transverse momentum between 20 and 50 GeV, it ranges between 49% and 67% with an efficiency of 85% for selecting hard-scatter jets. A case study is performed in Higgs boson production via the vector-boson fusion process, showing that these techniques mitigate the background growth due to additional proton–proton interactions, thus enhancing the reach for such signatures

Expression of coiled-coil protein 1, a novel gene downstream of FGF2, in the developing brain

Fibroblast growth factor 2 (FGF2) plays an important role in cortical development. However, the genes downstream of FGF2 that mediate its effect are largely unknown. We have performed a microarray screening of genes regulated by FGF2 using primary cortical neuron culture derived from embryonic day 14.5 (E14.5) mouse forebrains. In this study, we have analysed a previously uncharacterised gene encoding a 180-amino acid protein, hereby named ‘coiled-coil protein 1 (ccp1)’, that showed a modest up-regulation upon FGF2 stimulation. Northern blots and RT-PCR showed specific expression of ccp1 in multiple tissues including adult and embryonic brains. In situ hybridizations revealed that ccp1 was expressed in the cortical plate between Reelin and Tbr1-positive layers in the dorsal cortex at E15.5. Furthermore, the expression pattern of ccp1 at E13.5–E14.5 reflected some of the aspects of tangential migration of cortical progenitors during the early phase. We observed that the expressed ccp1 protein was localised to endo/lysosomal compartment in the cell body as well as to vesicles present in the processes of primary cortical neurons and oligodendrocyte cell line