DNALI1 interacts with the MEIG1/PACRG complex within the manchette and is required for proper sperm flagellum assembly in mice

The manchette is a transient and unique structure present in elongating spermatids and required for proper differentiation of the germ cells during spermatogenesis. Previous work indicated that the MEIG1/PACRG complex locates in the manchette and is involved in the transport of cargos, such as SPAG16L, to build the sperm flagellum. Here using co48 immunoprecipitation and pull-down approaches in various cell systems, we established that DNALI1, an axonemal component originally cloned from Chlamydomonas reinhardtii, recruits and stabilizes PACRG and we confirm in vivo, the co-localization of DNALI1 and PACRG in the manchette by immunofluorescence of elongating murine spermatids. We next generated mice with a specific deficiency of DNALI1 in male germ cells, and observed a dramatic reduction of the sperm cells, which results in male infertility. In addition, we observed that the majority of the sperm cells exhibited abnormal morphology including misshapen heads, bent tails, enlarged midpiece, discontinuous accessory structure, emphasizing the importance of DNALI1 in sperm differentiation. Examination of testis histology confirmed impaired spermiogenesis in the mutant mice. Importantly, while testicular levels of MEIG1, PACRG and SPAG16L proteins were unchanged in the Dnali1 mutant mice, their localization within the manchette was greatly affected, indicating that DNALI1 is required for the formation of the MEIG1/PACRG complex within the manchette. Interestingly, in contrast to MEIG1 and PACRG-deficient mice, the DNALI1-deficient mice also showed impaired sperm spermiation/individualization, suggesting additional functions beyond its involvement in the manchette structure. Overall, our work identifies 63 DNALI1 as a protein required for sperm development

Lipolysis drives expression of the constitutively active receptor GPR3 to induce adipose thermogenesis

Thermogenic adipocytes possess a therapeutically appealing, energy-expending capacity, which is canonically cold-induced by ligand-dependent activation of beta-adrenergic G protein-coupled receptors (GPCRs). Here, we uncover an alternate paradigm of GPCR-mediated adipose thermogenesis through the constitutively active receptor, GPR3. We show that the N terminus of GPR3 confers intrinsic signaling activity, resulting in continuous Gscoupling and cAMP production without an exogenous ligand. Thus, transcriptional induction of Gpr3 represents the regulatory parallel to ligand-binding of conventional GPCRs. Consequently, increasing Gpr3 expression in thermogenic adipocytes is alone sufficient to drive energy expenditure and counteract metabolic disease in mice. Gpr3 transcription is cold-stimulated by a lipolytic signal, and dietary fat potentiates GPR3-dependent thermogenesis to amplify the response to caloric excess. Moreover, we find GPR3 to be an essential, adrenergic-independent regulator of human brown adipocytes. Taken together, our findings reveal a noncanonical mechanism of GPCR control and thermogenic activation through the lipolysis-induced expression of constitutively active GPR3.Diabetes mellitus: pathophysiological changes and therap

Literature review on the assessment of masonry properties by tests on core samples

Starting point in this research is to find a quick and non-destructive method to characterize the mechanical properties of existing masonry. Tests on cylindrical cores have been recently introduced as a novel in-situ testing method to identify the properties of existing clay brick masonry. Currently, some researchers reported promising results, showing that the adopted methodology causes minor damage to the structures and it allows a direct estimation of the mechanical properties. To evaluate the mechanical properties of masonry, cores extracted perpendicular to the surface of a wall are subjected to the splitting tests, by which the compressive and shear properties of the masonry can be estimated. In the first case, previous studies adopted different core configurations (i.e. size and joint pattern) subjected to compressive load. In the second case, cores with only a single bed joint were used. In the literature, the coreswere tested in a way that the bed joint was rotated with respect to its original position. Consequently, a mixed compression–shear stress state is induced at the centre of the mortar joint

Computational modeling of the cyclic pushover test on a calcium silicate element masonry assemblage

Induced seismicity in the Groningen region of the Netherlands has led to a large scale testing campaign on Calcium silicate element masonry structures at Delft University of Technology. An overview of the finite element analysis (FEA) using an implicit solver, on the full scale quasi-static cyclic pushover test performed on a two-storey calcium sili-cate element masonry assemblage is presented in this paper. Tests have been performed in the experimental campaign at material, component, and structural level, of which the ma-terial tests like bond wrench tests, compression tests and shear tests are also briefed in this paper