BLOC-1 and BLOC-3 regulate VAMP7 cycling to and from melanosomes via distinct tubular transport carriers.

Endomembrane organelle maturation requires cargo delivery via fusion with membrane transport intermediates and recycling of fusion factors to their sites of origin. Melanosomes and other lysosome-related organelles obtain cargoes from early endosomes, but the fusion machinery involved and its recycling pathway are unknown. Here, we show that the v-SNARE VAMP7 mediates fusion of melanosomes with tubular transport carriers that also carry the cargo protein TYRP1 and that require BLOC-1 for their formation. Using live-cell imaging, we identify a pathway for VAMP7 recycling from melanosomes that employs distinct tubular carriers. The recycling carriers also harbor the VAMP7-binding scaffold protein VARP and the tissue-restricted Rab GTPase RAB38. Recycling carrier formation is dependent on the RAB38 exchange factor BLOC-3. Our data suggest that VAMP7 mediates fusion of BLOC-1-dependent transport carriers with melanosomes, illuminate SNARE recycling from melanosomes as a critical BLOC-3-dependent step, and likely explain the distinct hypopigmentation phenotypes associated with BLOC-1 and BLOC-3 deficiency in Hermansky-Pudlak syndrome variants.This work was supported by grants from the National Institutes of Health, National Eye Institute (R01 EY015625, to M.S. Marks and G.  Raposo), National Institute of Arthritis and Musculoskeletal and Skin Diseases (R01 AR048155, to M.S. Marks, and F32 AR062476, to M.K. Dennis), National Institute of General Medical Sciences (R01 GM108807, to M.S. Marks); Fondation pour la Recherche Médicale (to T.  Galli); the UK Medical Research Council (G0900113, to J.P. Luzio); and the Wellcome Trust (108429, to E.V. Sviderskaya and D.C. Bennett). This work was also supported by a Canadian Institutes of Health Research Fellowship (to G.G.  Hesketh) and a Fondation pour la Recherche Médicale grant from Centre National de la Recherche Scientifique, Institut National de la Santé et de la Recherche Médicale, Institut Curie, and Fondation pour la Recherche Médicale (DEQ20140329491 Team label, to G. Raposo).This is the final version of the article. It first appeared from Rockefeller University Press via http://dx.doi.org/10.1083/jcb.20160509

Use of antenatal services and delivery care among women in rural western Kenya: a community based survey

BACKGROUND: Improving maternal health is one of the UN Millennium Development Goals. We assessed provision and use of antenatal services and delivery care among women in rural Kenya to determine whether women were receiving appropriate care. METHODS: Population-based cross-sectional survey among women who had recently delivered. RESULTS: Of 635 participants, 90% visited the antenatal clinic (ANC) at least once during their last pregnancy (median number of visits 4). Most women (64%) first visited the ANC in the third trimester; a perceived lack of quality in the ANC was associated with a late first ANC visit (Odds ratio [OR] 1.5, 95% confidence interval [CI] 1.0–2.4). Women who did not visit an ANC were more likely to have < 8 years of education (adjusted OR [AOR] 3.0, 95% CI 1.5–6.0), and a low socio-economic status (SES) (AOR 2.8, 95% CI 1.5–5.3). The ANC provision of abdominal palpation, tetanus vaccination and weight measurement were high (>90%), but provision of other services was low, e.g. malaria prevention (21%), iron (53%) and folate (44%) supplementation, syphilis testing (19.4%) and health talks (14.4%). Eighty percent of women delivered outside a health facility; among these, traditional birth attendants assisted 42%, laypersons assisted 36%, while 22% received no assistance. Factors significantly associated with giving birth outside a health facility included: age ≥ 30 years, parity ≥ 5, low SES, < 8 years of education, and > 1 hour walking distance from the health facility. Women who delivered unassisted were more likely to be of parity ≥ 5 (AOR 5.7, 95% CI 2.8–11.6). CONCLUSION: In this rural area, usage of the ANC was high, but this opportunity to deliver important health services was not fully utilized. Use of professional delivery services was low, and almost 1 out of 5 women delivered unassisted. There is an urgent need to improve this dangerous situation

"Dem Leben auf der Spur" - Die biologischen Forschungen Alexander von Humboldts

Article in German

„Vater einer großen Nachkommenschaft von Forschungsreisenden ...“ Ehrungen Alexander von Humboldts im Jahre 1869

Article in German, Abstracts in English and GermanIn 1869 the “Naturwissenschaftlicher Verein” was founded in Magdeburg (Saxony Anhalt). That was the time when the scientific world celebrated Alexander von Humboldt’s 100th birthday. In this context, Humboldt’s achievements were remembered during the founding ceremony of that society. The paper which was read in September 2003 on a meeting of this organisation, focuses on three famous naturalists who celebrated Humboldt because they owed him much help in their own professional careers. The botanist Matthias Jacob Schleiden gave a memorial speech in 1869 in Dresden. The physiologist and pioneer of electro-biology Emil du Bois-Reymond honoured his mentor A. v. Humboldt on the occasion of the dedication of the statues of Wilhelm and Alexander in 1883 in Berlin. Charles Darwin expressed his gratitude to Humboldt by sending him in 1839 the report of his travels and received an interesting reply. These three scholars represented a new epoch in the development of the natural sciences. The paper includes a recently re-discovered letter from Humboldt to Schleiden, dated April 13, 1842