Tango1 spatially organizes ER exit sites to control ER export.

Exit of secretory cargo from the endoplasmic reticulum (ER) takes place at specialized domains called ER exit sites (ERESs). In mammals, loss of TANGO1 and other MIA/cTAGE (melanoma inhibitory activity/cutaneous T cell lymphoma-associated antigen) family proteins prevents ER exit of large cargoes such as collagen. Here, we show that Drosophila melanogaster Tango1, the only MIA/cTAGE family member in fruit flies, is a critical organizer of the ERES-Golgi interface. Tango1 rings hold COPII (coat protein II) carriers and Golgi in close proximity at their center. Loss of Tango1, present at ERESs in all tissues, reduces ERES size and causes ERES-Golgi uncoupling, which impairs secretion of not only collagen, but also all other cargoes we examined. Further supporting an organizing role of Tango1, its overexpression creates more and larger ERESs. Our results suggest that spatial coordination of ERES, carrier, and Golgi elements through Tango1's multiple interactions increases secretory capacity in Drosophila and allows secretion of large cargo.

[Epidemiological study on developmental delay of 18-month-old children from four districts/counties in Beijing].

OBJECTIVE: To investigate epidemiological characteristics of prevalence, impact factors and etiology on developmental delay of 18-month-old children from four districts/counties in Beijing. METHODS: An epidemiological study on developmental delay was designed to investigate all the 18-month-old children enrolled from Shunyi,Daxing,Miyun and Yanqing districts/counties in Beijing from May to September, 2011. Combining the tertiary network of child health with hospital clinical study was used. Child developmental questionnaires were completed by doctors in communities of the first network of child health. Gesell Developmental Schedules for children with Denver developmental screening test (DDST) screening positive results were assessed by doctors in districts/counties hospitals of the second network of child health. The children diagnosed as developmental delay were transferred to the tertiary hospitals of the third network of child health for further etiological diagnosis, follow-up and developmental evaluation. The case-control study compared between children with/without developmental delay were performed in accordance with the 1:4 ratios by gender and residence community matched. SPSS 16.0 was adopted for data analysis of the case-control study. RESULTS: A total of 3 182 children were screened among the 4 037 children fitting the criteria,and the coverage rate was 78.8% (3 182/4 037). Of the 3 182 screened children, 22 children were diagnosed as developmental delay. The prevalence rate was 6.91 ‰ (22/3 182). Out of the 22 children with developmental delay, 15 were boys and 7 were girls. The sex ratio was 2.1:1. The prevalence rates of the children with developmental delay in Shunyi, Daxing, Miyun and Yanqing were 3.45 ‰ (4/1 160), 4.50 ‰(5/1 111), 15.87 ‰(7/441) and 12.77 ‰ (6/479), respectively. The results from one-way ANOVA analysis showed the main risk factors in children with developmental delay included low-income families, mothers' low educational level, small size for gestational age infant, multiple fetuses, serious diseases after birth, congenital malformations and physical retardation (P<0.05). CONCLUSION: The screening coverage rate of this study is 78.8%. The prevalence rate of children with developmental delay is 6.91 ‰, which is significantly different in sex ratio and districts of the subjects. The etiology of developmental delay might be associated with social-economic and biological factors.