ER-to-Golgi trafficking of procollagen in the absence of large carriers

AbstractSecretion and assembly of collagen is fundamental to the function of the extracellular matrix. Defects in the assembly of a collagen matrix lead to pathologies including fibrosis and osteogenesis imperfecta. Owing to the size of fibril-forming procollagen molecules it is assumed that they are transported from the endoplasmic reticulum to the Golgi in specialised large COPII-dependent carriers. Here, analysing endogenous procollagen and a new engineered GFP-tagged form, we show that transport to the Golgi occurs in the absence of large carriers. Large GFP-positive structures are observed occasionally but these are non-dynamic, are not COPII-positive, and label with markers of the ER. We propose a “short-loop” model of COPII-dependent ER-to-Golgi traffic that, while consistent with models of ERGIC-dependent expansion of COPII carriers, does not invoke long-range trafficking of large vesicular structures. Our findings provide an important insight into the process of procollagen trafficking and reveal a short-loop pathway from the ER to the Golgi, without the use of large carriers.SummaryTrafficking of procollagen is essential for normal cell function. Here, imaging of GFP-tagged type I procollagen reveals that it is transported from the endoplasmic reticulum to the Golgi, without the use of large carriers.</jats:sec

Neospora caninum associated with epidemic abortions in dairy cattle: The first clinical neosporosis report in Turkey

YILDIZ, Kader/0000-0001-5802-6156WOS: 000262663600011PubMed: 19028014Neospora caninum, a protozoan parasite, has been considered as one of the most important etiological agents responsible for abortion in dairy cattle throughout the world since it was first identified in dogs in 1988. In this report, characteristics of neosporosis, detected in a dairy cow ranch having epidemic abortions as high as 18.4%, were described. Blood samples were collected from 25 infertile or aborted dairy cattle, 6 calves born in 2006 and 40 heifers that were born in 2005 and raised in the same ranch. Necropsy was conducted in a 20-day-old Simmental calf that exhibited neurological signs including incoordination, head shaking, hyperextension in forelimbs and hindlimbs and tremor. The seroprevalance in aborted or infertile dairy cattle, heifers, and calves was 60%, 40%, and 33.3%, respectively. The mothers of seropositive two calves including clinically affected calf and its dam were N. caninum seropositive. In immunoperoxidase examinations, N. caninum antigen immunopositivity was observed in the degenerative and necrotic neurons in the brain, cerebellum as well as neurons in dorsal root ganglia of the cervical and thoracic regions of the spinal cord. In the heart, myocytes and Purkinje cells exhibited granular and linear patterns of immunoreactivity. Striated myofibers around the eyeball also showed immunolocalization for N. caninum antigen. Ultrastructurally, tachyzoites with typical apical complex, rhoptries and (double-layered parasitic membrane Were detected in the brain and heart sections. In conclusion, this report described clinical neosporosis for the first time in Turkey with tissue localization of the causative agents. This scientific communication also discusses the possible impact of cattle neosporosis by clinical, serologic and pathologic evidences collected from the Survey of calves born in two successive generations in a ranch. Crown Copyright (c) 2008 Published by Elsevier B.V. All rights reserved.Kirikkale University Scientific Research Council projectKirikkale University [2005/16]This study was conducted as a part of N. caninum screening project supported by Kirikkale University Scientific Research Council project (Project no: 2005/16). The authors thank Veterinary Surgeon M. Sava Akkaya and Mehmet Varol for their invaluable contributions to the screening project

Factors contributing to sex assignment and reassignment decisions in Turkish children with 46,XY disorders of sex development

Yilmaz, Savas/0000-0003-2540-5808; berberoglu, merih/0000-0003-3102-0242WOS: 000250537900008PubMed: 18038709Background. Sex assignment decisions for children with disorders of sex development (DSD) should be based on integrative assessments of relevant biological and psychosocial characteristics. Aim: To investigate the factors that contributed to sex assignment decisions for children with 46,XY DSD. Patients: Sixty-one children recruited from a clinical sample were evaluated. Methods: Findings of endocrinological and psychiatric evaluations were entered into a logistic regression analysis. Results: Gender identity was the strongest correlate of assigned sex. External genital under-virilization, sex announced at birth and toy/ activity preferences were predominant predictors. Twelve children, six of whom were prepubertal, were reassigned to male sex. Conclusions: Psychological factors seem to be as influential on sex reassignment decisions as are endocrinological and social factors, especially if the disorder is diagnosed at an older age. Prepubertal gender conversion is possible, which implies the importance of follow-up during childhood