Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | PubMed Central |
|---|---|
| Abstract | A protein activity has been identified in extracts of coated vesicles that enables purified clathrin triskelions to reassemble in vitro into coat structures of uniform size. Coats formed in the presence of this preparation, regardless of the buffer system employed, are uniform in size with a mean diameter of 78 nm (+/- 5 nm SD) and a sedimentation coefficient (S20,w) of approximately 250S. Analysis of the reassembled coats on dodecyl sulfate acrylamide gels reveals that they have specifically incorporated three polypeptides from the preparation: those of Mr congruent to 52,000, 100,000, and 110,000. The 52,000-, 100,000-, and 110,000-mol-wt polypeptides are incorporated in molar ratios of 0.85, 1.11, and 0.26, respectively, per three clathrin monomers (equivalent to one triskelion). We therefore designate these as assembly polypeptides (AP). In contrast, coats formed from clathrin alone, under permissive buffer conditions, are larger (400S), more heterogeneous in size (101 nm +/- 15 nm SD), and are composed only of clathrin and its associated light chains. These biochemical and biophysical characteristics distinguish AP-reassembled coats from coats formed by triskelions alone. AP-reassembled coats can be isolated, dissociated, then reassembled in the absence of any other factors. This recycling indicates that all the information needed for reassembly is present in the coat-incorporated polypeptides themselves. Reassembly is stoichiometric and saturable with respect to both clathrin and AP concentration. In the presence of AP, significant coat reassembly occurs at clathrin concentrations as low as 0.06 mg/ml. AP-mediated reassembly proceeds at 4 degrees, 22 degrees, and 37 degrees C. Coat formation also proceeds efficiently at intracellular pH values (7.2- 7.5) in the presence of AP. In its absence, reassembly does not occur at all above pH 6.7. In summary, AP promotes clathrin reassembly into coat structures of uniform size and distinctive composition under physiologically relevant salt, temperature, and pH conditions. In addition, the close similarity in size between AP-reassembled coats in vitro and coated membranes in the Golgi region in vivo raises the possibility that AP in the cell may be associated with this subpopulation of coat structures. |
| Starting Page | 1339 |
| File Format | |
| ISSN | 15408140 |
| e-ISSN | 15408140 |
| Journal | The Journal of Cell Biology |
| Issue Number | 5 |
| Volume Number | 97 |
| Language | English |
| Publisher | The Rockefeller University Press |
| Publisher Date | 1983-11-01 |
| Access Restriction | Open |
| Rights Holder | The Rockefeller University Press |
| Subject Keyword | Research in Higher Education |
| Content Type | Text |
| Resource Type | Article |
| Subject | Cell Biology Medicine |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|