Aims. We present a study of a large filamentary structure at z ∼ 0.73 in the field of the COSMOS survey, the so-called COSMOS Wall. This structure encompasses a comprehensive range of environments from a dense cluster and a number of galaxy groups to filaments, less dense regions, and adjacent voids. It thus provides a valuable laboratory for the accurate mapping of environmental effects on galaxy evolution at a look-back time of ∼6.5 Gyr, when the Universe was roughly half its present age. Methods. We performed deep spectroscopic observations with VIMOS at VLT of a K-band selected sample of galaxies in this complex structure, building a sample of galaxies complete in galaxy stellar mass down to a lower limit of log(M * /M ) ∼ 9.8, which is significantly deeper than previously available data. Thanks to its location within the COSMOS survey, each galaxy benefits from a wealth of ancillary information: HST-ACS data with I-band exposures down to I AB ∼ 28 complemented by extensive multiwavelength ground-and space-based observations spanning the entire electromagnetic spectrum. Results. In this paper we detail the survey strategy and weighting scheme adopted to account for the biases introduced by the photometric preselection of our targets. We present our galaxy stellar mass and rest-frame magnitudes estimates together with a group catalog obtained with our new data and their member galaxies color/mass distribution. Conclusions. Owing to our new sample we can perform a detailed, high definition mapping of the complex COSMOS Wall structure. The sharp environmental information, coupled with high quality spectroscopic information and rich ancillary data available in the COSMOS field, enables a detailed study of galaxy properties as a function of local environment in a redshift slice where environmental effects are important, and in a stellar mass range where mass and environment driven effects are both at work.

Bone morphogenetic protein 1 (BMP-1), which is a tolloid member of the astacin-like family of zinc metalloproteinases, is a highly effective procollagen C-proteinase (PCP) and chordinase. On the other hand, mammalian tolloid like-2 (mTLL-2) does not cleave chordin or procollagen; procollagen is cleaved by mTLL-2 in the presence of high levels of procollagen C-proteinase enhancer-1 (PCPE-1), for reasons that are unknown. We used these differences in activity between BMP-1 and mTLL-2 to narrow in on the domains in BMP-1 that specify PCP and chordinase activity. Using a domain swap approach, we showed that: 1) the metalloproteinase and CUB2 domains of BMP-1 are absolutely required for PCP activity; swaps with either of the corresponding domains in BMP-1 and mTLL-2 did not result in procollagen cleavage and 2) the proteinase domain of mTLL-2 can cleave chordin if coupled to the CUB1 domain of BMP-1. Therefore, the minimal structure for chordinase activity comprises a metalloproteinase domain (either from BMP-1 or from mTLL-2) and the CUB1 domain of BMP-1 (the CUB1 domain of mTLL-2 cannot substitute for the CUB1 domain of BMP-1). We showed that the minimal procollagen C-proteinase (BMP-1 lacking the EGF and CUB3 domain) was enhanced by PCPE-1 but not as well as BMP-1 retaining the CUB3 domain. Further studies showed that PCPE-1 had no effect on the ability of BMP-1 to cleave chordin. The data support a previously suggested mechanism of PCPE-1 whereby PCPE-1 interacts with procollagen, but in addition, the CUB3 domain of BMP-1 appears to augment the interaction.Tolloids are a small group of highly conserved astacin-like zinc metalloproteinases that occur in all metazoa, from flies to humans. They are essential for normal development because they cleave precursors of extracellular matrix macromolecules (at least in vertebrates) and antagonists of bone morphogenetic proteins (in flies, worms, and vertebrates). By cleaving precursors of extracellular matrix macromolecules (see below for details), tolloids initiate the assembly of tissues. How tolloids distinguish between different substrates is not well understood.BMP-1, 1 which is one of the best studied tolloids, was originally isolated from osteogenic extracts of bone (1-3) and is a small splice variant of the bmp1 gene. The larger splice variant of the bmp1 gene is mammalian tolloid (mTLD). Two additional genes give rise to two further tolloid proteinases in vertebrates, namely mammalian tolloid like-1 (mTLL-1) and -2 (mTLL-2) (4, 5). BMP-1, mTLD, mTLL-1, and mTLL-2 have (from the N terminus) a signal peptide, a prodomain, an astacin-like metalloproteinase domain, two consecutive CUB domains, an EGFlike domain, and a third CUB domain. mTLD, mTLL-1, and mTLL-2 have an additional EGF-like domain and two additional CUB domains (6). All proteins have a unique short sequence at the C terminus. The amino acid sequences immediately N-terminal of the metalloproteinase domains of tolloids contain a consensus cleavage site for furin-like proprotein convertases. Subsequently, i...

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Aims. We study the ionized gas emission from the large scale shock region of Stephan's Quintet (SQ). Methods. We carried out integral field unit (IFU) optical spectroscopy on three pointings in and near the SQ shock. We used Potsdam MultiAperture Spectrometer (PMAS) on the 3.5 m Calar Alto telescope to obtain measures of emission lines that provide insight into physical properties of the gas. Severe blending of Hα and [Nii]λ6548, 6583 Å emission lines in many spaxels required the assumption of at least two kinematical components to extract fluxes for the individual lines. Results. The main results from our study include (a) detection of discrete emission features in the new intruder velocity range 5400-6000 km s −1 showing properties consistent with Hii regions, (b) detection of a low-velocity component spanning the range 5800−6300 km s −1 with properties resembling a solar-metallicity shocked gas and (c) detection of a high-velocity component at ≈6600 km s −1 with properties consistent with those of a low-metallicity shocked gas. Conclusions. The two shocked components are interpreted as products of a collision between NGC 7318b new intruder and a debris field in its path. This has given rise to a complex structure of ionized gas where several components with different kinematical and physical properties coexist, although part of the original interstellar medium (ISM) associated with NGC 7318b is still present and remains unaltered. Our observations suggest that the low-velocity ionized component might have existed before the new intruder collision and could be associated with the NW-LV Hi component. The high-velocity ionized component might fill the gap between the Hi complexes observed in SQ-A and NGC 7319's tidal filament (NW-HV, Arc-N and Arc-S in Williams et al. 2002, AJ, 123, 2417.