French and Asian subsets of chicken breeds were first analysed using 22 microsatellites and then compared to the AVIANDIV European set using 14 loci. Positive correlations were observed between F(IT) or F(ST) and typological values or variance of markers using the multivariate analysis mcoa. The first axis of the multivariate representation separated Asian from European breeds, revealing breeds with Asian ancestor. Using all or 14 loci, correct assignation rate was always higher than 93%. The Weitzman index and the aggregate diversity D were calculated using 22 loci within French and Asian breeds. The French breed Coucou de Rennes and the Hua-Tung breed seemed to contribute the most to the global diversity of each subset. This approach on French-only breeds and then on French with AVIANDIV domestic breeds (14 loci) showed that the Marans breed contributed the most. The AVIANDIV framework could be useful to evaluate the genetic diversity of local breeds and to help in connecting national and regional conservation policies.

Bone-marrow-derived mesenchymal stem cells (MSCs) constitute an interesting cellular source to promote brain regeneration after neurodegenerative diseases. Recently, several studies suggested that oxygen-dependent gene expression is of crucial importance in governing the essential steps of neurogenesis such as cell proliferation, survival and differentiation. In this context, we analysed the effect of the HIF-1 (hypoxia inducible factor-1) activation-mimicking agent CoCl2 on MSCs. CoCl2 treatment increased the expression of the anti-proliferative gene BTG2/PC3 and decreased cyclin D1 expression. Expression of HIF-1α and its target genes EPO, VEGF and p21 was also upregulated. These changes were followed by inhibition of cell proliferation and morphological changes resulting in neuron-like cells, which had increased neuronal marker expression and responded to neurotransmitters. Echinomycin, a molecule inhibiting HIF-1 DNA-binding activity, blocked the CoCl2 effect on MSCs. Additionally, by using Y-27632, we demonstrated that Rho kinase (ROCK) inhibition potentiated CoCl2-induced MSC differentiation in particular into dopaminergic neuron-like cells as attested by its effect on tyrosine hydroxylase expression. Altogether, these results support the ability of MSCs to differentiate into neuron-like cells in response to CoCl2, an effect that might act, in part, through HIF-1 activation and cell-cycle arrest, and which is potentiated by inhibition of ROCK.

MAT II, the extrahepatic form of methionine adenosyltransferase (MAT), consists of catalytic ␣ 2 /␣ 2 subunits and a noncatalytic ␤ subunit, believed to have a regulatory function. The full-length cDNA that encodes the ␤ subunit of human MAT II was cloned and found to encode for a 334-amino acid protein with a calculated molecular weight of 37,552. Analysis of sequence homology showed similarity with bacterial enzymes that catalyze the reduction of TDP-linked sugars. The ␤ subunit cDNA was cloned into the pQE-30 expression vector, and the recombinant His tagged protein, which was expressed in Escherichia coli, was recognized by antibodies to the human MAT II, to synthetic peptides copying the sequence of native ␤ subunit protein, and to the r␤ protein. There is no cross-reactivity between the MAT II ␣ 2 or ␤ subunits. None of the anti-␤ subunit antibodies reacted with protein extracts of E. coli host cells, suggesting that these bacteria have no ␤ subunit protein. Interestingly, the r␤ subunit associated with E. coli as well as human MAT ␣ subunits. This association changed the kinetic properties of both enzymes and lowered the K m of MAT for L-methionine. Together, the data show that we have cloned and expressed the human MAT II ␤ subunit and confirmed its long suspected regulatory function. This knowledge affords a molecular means by which MAT activity and consequently the levels of AdoMet may be modulated in mammalian cells.Methionine adenosyltransferase (MAT; S-adenosyl-L-methionine synthetase, EC 2.5.1.6) 1 is an essential enzyme that catalyzes the synthesis of S-adenosylmethionine (AdoMet) from L-methionine (L-Met) and ATP (1, 2). AdoMet is the major methyl group donor, participating in the methylation of proteins, DNA, RNA, phospholipids, and other small molecules (reviewed in Refs. 3-5). In addition, AdoMet is the ultimate source of the propylamine moiety used in polyamine biosynthesis, and it serves as co-factor for other key enzymes in the one-carbon metabolism pathway (3-5). MAT is present in all living species, including thermophilic archaebacteria, plants, yeast, and mammals (reviewed in Refs. 4 and 6 -8). Interestingly, most species have more than one MAT isozyme (6).In mammals, it is now established that there are at least two MAT isozymes (9 -12). MAT I/III is expressed only in liver and has a catalytic subunit designated ␣ 1 that is encoded by the MAT1A gene (8, 9, 13-16). MAT I and MAT III represent different oligomeric forms of the ␣ 1 subunit -MAT III is a dimer, and MAT I is a tetramer of the ␣ 1 subunit (9, 17-19). MAT I and MAT III differ considerably in their physical, kinetic, and regulatory properties (8,9,20). The MAT II isozyme is expressed in all tissues, including the liver, and has been studied in many tissues including erythrocytes, lymphocytes, brain, kidney, testis, and fetal liver (11, 20 -27).We have been characterizing the human MAT II from human lymphocytes (22, 28 -31) 2 and were able to show that the form present in activated lymphocytes consists of distinct subunits (22...

The balance between tissue-type plasminogen activator (tPA) and one of its inhibitors, neuroserpin, has crucial roles in the central nervous system, including the control of neuronal migration, neuronal plasticity and neuronal death. In the present study, we demonstrate that the activation of the transforming growth factor-β (TGFβ)-related BMPR-IB (also known as BMPR1B and Alk6)- and Smad5-dependent signalling pathways controls neuroserpin transcription. Accordingly, we demonstrate for the first time that anti-Mullerian hormone (AMH), a member of the TGFβ family, promotes the expression of neuroserpin in cultured neurons but not in astrocytes. The relevance of these findings is confirmed by the presence of both AMH and AMH type-II receptor (AMHR-II) in brain tissues, and is supported by the observation of reduced levels of neuroserpin in the brain of AMHR-II-deficient mice. Interestingly, as previously demonstrated for neuroserpin, AMH protects neurons against N-methyl-D-aspartate (NMDA)-mediated excitotoxicity both in vitro and in vivo. This study demonstrates the existence of an AMH-dependent signalling pathway in the brain leading to an overexpression of the serine-protease inhibitor, neuroserpin, and neuronal survival.