Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC
Summary Dgp71WD/Nedd1 proteins are essential for mitotic spindle formation. In human cells, Nedd1 targets γ-tubulin to both centrosomes and spindles, but in other organisms the function of Dgp71WD/Nedd1 is less clear. In Drosophila cells, Dgp71WD plays a major part in targeting γ-tubulin to spindles...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
The Company of Biologists
2012-03-01
|
| Series: | Biology Open |
| Subjects: | |
| Online Access: | http://bio.biologists.org/content/1/5/422 |
| _version_ | 1830308451029352448 |
|---|---|
| author | Richard F. Reschen Nathalie Colombie Lucy Wheatley Jeroen Dobbelaere Daniel St Johnston Hiro Ohkura Jordan W. Raff |
| author_facet | Richard F. Reschen Nathalie Colombie Lucy Wheatley Jeroen Dobbelaere Daniel St Johnston Hiro Ohkura Jordan W. Raff |
| author_sort | Richard F. Reschen |
| collection | DOAJ |
| description | Summary
Dgp71WD/Nedd1 proteins are essential for mitotic spindle formation. In human cells, Nedd1 targets γ-tubulin to both centrosomes and spindles, but in other organisms the function of Dgp71WD/Nedd1 is less clear. In Drosophila cells, Dgp71WD plays a major part in targeting γ-tubulin to spindles, but not centrosomes, while in Xenopus egg extracts, Nedd1 acts as a more general microtubule (MT) organiser that can function independently of γ-tubulin. The interpretation of these studies, however, is complicated by the fact that some residual Dgp71WD/Nedd1 is likely present in the cells/extracts analysed. Here we generate a Dgp71WD null mutant lacking all but the last 12 nucleotides of coding sequence. The complete loss of Dgp71WD has no quantifiable effect on γ-tubulin or Centrosomin recruitment to the centrosome in larval brain cells. The recruitment of γ-tubulin to spindle MTs, however, is severely impaired, and spindle MT density is reduced in a manner that is indistinguishable from cells lacking Augmin or γ-TuRC function. In contrast, the absence of Dgp71WD leads to defects in the assembly of the acentrosomal female Meiosis I spindle that are more severe than those seen in Augmin or γ-TuRC mutants, indicating that Dgp71WD has additional functions that are independent of these complexes in oocytes. Moreover, the localisation of bicoid RNA during oogenesis, which requires γ-TuRC function, is unperturbed in Dgp71WD120 mutants. Thus, Dgp71WD is not simply a general cofactor required for γ-TuRC and/or Augmin targeting, and it appears to have a crucial role independent of these complexes in the acentrosomal Meiosis I spindle. |
| first_indexed | 2024-12-19T10:49:46Z |
| format | Article |
| id | doaj.art-037d4d585d25486cb57e8d53059fb3d6 |
| institution | Directory Open Access Journal |
| issn | 2046-6390 |
| language | English |
| last_indexed | 2024-12-19T10:49:46Z |
| publishDate | 2012-03-01 |
| publisher | The Company of Biologists |
| record_format | Article |
| series | Biology Open |
| spelling | doaj.art-037d4d585d25486cb57e8d53059fb3d62022-12-21T20:25:03ZengThe Company of BiologistsBiology Open2046-63902012-03-011542242910.1242/bio.20125962012596Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRCRichard F. Reschen0Nathalie Colombie1Lucy Wheatley2Jeroen Dobbelaere3Daniel St Johnston4Hiro Ohkura5Jordan W. Raff6 Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK Wellcome Trust Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Mayfield Road, Edinburgh, EH9 3JR, UK Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK Research Institute of Molecular Pathology (IMP), Dr. Bohr-Gasse 7, 1030 Vienna, Austria Gurdon Institute, University of Cambridge, Tennis Court Road, Cambridge, CB2 1QN, UK Wellcome Trust Centre for Cell Biology, University of Edinburgh, Michael Swann Building, Kings Buildings, Mayfield Road, Edinburgh, EH9 3JR, UK Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, UK Summary Dgp71WD/Nedd1 proteins are essential for mitotic spindle formation. In human cells, Nedd1 targets γ-tubulin to both centrosomes and spindles, but in other organisms the function of Dgp71WD/Nedd1 is less clear. In Drosophila cells, Dgp71WD plays a major part in targeting γ-tubulin to spindles, but not centrosomes, while in Xenopus egg extracts, Nedd1 acts as a more general microtubule (MT) organiser that can function independently of γ-tubulin. The interpretation of these studies, however, is complicated by the fact that some residual Dgp71WD/Nedd1 is likely present in the cells/extracts analysed. Here we generate a Dgp71WD null mutant lacking all but the last 12 nucleotides of coding sequence. The complete loss of Dgp71WD has no quantifiable effect on γ-tubulin or Centrosomin recruitment to the centrosome in larval brain cells. The recruitment of γ-tubulin to spindle MTs, however, is severely impaired, and spindle MT density is reduced in a manner that is indistinguishable from cells lacking Augmin or γ-TuRC function. In contrast, the absence of Dgp71WD leads to defects in the assembly of the acentrosomal female Meiosis I spindle that are more severe than those seen in Augmin or γ-TuRC mutants, indicating that Dgp71WD has additional functions that are independent of these complexes in oocytes. Moreover, the localisation of bicoid RNA during oogenesis, which requires γ-TuRC function, is unperturbed in Dgp71WD120 mutants. Thus, Dgp71WD is not simply a general cofactor required for γ-TuRC and/or Augmin targeting, and it appears to have a crucial role independent of these complexes in the acentrosomal Meiosis I spindle.http://bio.biologists.org/content/1/5/422Dgp71WDCentrosomeMitosisMeiosis |
| spellingShingle | Richard F. Reschen Nathalie Colombie Lucy Wheatley Jeroen Dobbelaere Daniel St Johnston Hiro Ohkura Jordan W. Raff Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC Biology Open Dgp71WD Centrosome Mitosis Meiosis |
| title | Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC |
| title_full | Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC |
| title_fullStr | Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC |
| title_full_unstemmed | Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC |
| title_short | Dgp71WD is required for the assembly of the acentrosomal Meiosis I spindle, and is not a general targeting factor for the γ-TuRC |
| title_sort | dgp71wd is required for the assembly of the acentrosomal meiosis i spindle and is not a general targeting factor for the γ turc |
| topic | Dgp71WD Centrosome Mitosis Meiosis |
| url | http://bio.biologists.org/content/1/5/422 |
| work_keys_str_mv | AT richardfreschen dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT nathaliecolombie dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT lucywheatley dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT jeroendobbelaere dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT danielstjohnston dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT hiroohkura dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc AT jordanwraff dgp71wdisrequiredfortheassemblyoftheacentrosomalmeiosisispindleandisnotageneraltargetingfactorforthegturc |