title: Drosophila oocyte polarity and cytoskeleton organization require regulation of Ik2 activity by Spn-F and Javelin-like.
abstract: The Drosophila melanogaster Spn-F, Ik2, and Javelin-like (Jvl) proteins interact to regulate oocyte mRNA localization and cytoskeleton organization. However, the mechanism by which these proteins interact remains unclear. Using antibodies to activated Ik2, we showed that this protein is found at the region of oocyte and follicle cell where microtubule minus ends are enriched. We demonstrate that germ line Ik2 activation is diminished both in jvl and in spn-F mutant ovaries. Structure-function analysis of Spn-F revealed that the C-terminal end is critical for protein function, since it alone was able to rescue spn-F sterility. On the other hand, germ line expression of Spn-F lacking its conserved C-terminal region (Spn-FΔC) phenocopied ik2, leading to production of ventralized eggshell and bicaudal embryos. In Spn-FΔC-expressing oocytes, Gurken protein is mislocalized and oskar mRNA and protein localization is disrupted. Expression of Ik2 rescued Spn-FΔC ovarian phenotypes. We found that whereas Spn-F physically interacts with Ik2 and Jvl, Spn-FΔC physically interacts with Ik2 but not with Jvl. Thus, expression of Spn-FΔC, which lacks the Jvl-interacting domain, probably interferes with interaction of Ik2 and Jvl. In summary, our results demonstrate that Spn-F mediates the interaction between Ik2 and Jvl to control Ik2 activity.
authors.affiliation: Department of Life Sciences, Ben-Gurion University, Beer-Sheva, Israel.
authors.forename: Simha
authors.initials: S
authors.lastname: Amsalem
authors.forename: Anna
authors.initials: A
authors.lastname: Bakrhat
authors.forename: Tetsuhisa
authors.initials: T
authors.lastname: Otani
authors.forename: Shigeo
authors.initials: S
authors.lastname: Hayashi
authors.forename: Bareket
authors.initials: B
authors.lastname: Goldstein
authors.forename: Uri
authors.initials: U
authors.lastname: Abdu
mesh_terms: D000199:Actins / Q000378:metabolism; D000818:Animals; D016764:Cell Polarity; D003599:Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure; D029721:Drosophila Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000166:cytology* / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D017344:Genes, Insect; D051550:I-kappa B Kinase / Q000235:genetics / Q000378:metabolism*; D008840:Microfilament Proteins / Q000235:genetics / Q000378:metabolism*; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism*; D008870:Microtubules / Q000378:metabolism; D009154:Mutation; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D010766:Phosphorylation; D060066:Protein Interaction Maps; D012333:RNA, Messenger / Q000235:genetics; D016211:Transforming Growth Factor alpha / Q000032:analysis / Q000378:metabolism
chemical_list: D000199:Actins; D029721:Drosophila Proteins; D008840:Microfilament Proteins; D008869:Microtubule-Associated Proteins; D012333:RNA, Messenger; C510862:Spn-F protein, Drosophila; D016211:Transforming Growth Factor alpha; C083730:grk protein, Drosophila; C585109:jvl protein, Drosophila; C091675:osk protein, Drosophila; D051550:I-kappa B Kinase; C510861:IKKepsilon protein, Drosophila
references.citation: Genes Dev. 1998 Jun 1;12(11):1652-64
references.pmid: 9620852
references.citation: Science. 2000 Sep 22;289(5487):2120-2
references.pmid: 11000113
references.citation: Cell. 2008 Sep 5;134(5):843-53
references.pmid: 18775316
references.citation: Nature. 1980 Oct 30;287(5785):795-801
references.pmid: 6776413
references.citation: Science. 1982 Oct 22;218(4570):341-7
references.pmid: 6289435
references.citation: EMBO J. 1995 May 1;14(9):2043-55
references.pmid: 7538070
references.citation: Cell. 1992 Sep 4;70(5):849-59
references.pmid: 1516136
references.citation: PLoS Genet. 2008 Jul 18;4(7):e1000126
references.pmid: 18797514
references.citation: Development. 2002 Dec;129(23):5473-85
references.pmid: 12403717
references.citation: Nature. 2001 Dec 6;414(6864):611-6
references.pmid: 11740552
references.citation: Curr Biol. 2006 Aug 8;16(15):1531-7
references.pmid: 16887350
references.citation: Mol Cell Biol. 2010 Jan;30(2):496-507
references.pmid: 19917727
references.citation: BMC Cell Biol. 2008 Sep 17;9:51
references.pmid: 18796167
references.citation: PLoS One. 2012;7(5):e38010
references.pmid: 22666434
references.citation: EMBO J. 1988 Jun;7(6):1749-56
references.pmid: 2901954
references.citation: Development. 2006 Apr;133(8):1477-84
references.pmid: 16540510
references.citation: Genetics. 2007 Nov;177(3):1691-702
references.pmid: 18039880
references.citation: Nat Cell Biol. 2002 Aug;4(8):592-8
references.pmid: 12134163
references.citation: Dev Biol. 2009 Apr 1;328(1):160-72
references.pmid: 19389362
references.citation: Development. 1997 Jan;124(2):461-70
references.pmid: 9053322
references.citation: Curr Biol. 2009 Jun 23;19(12):1058-63
references.pmid: 19481457
references.citation: Cell. 1989 Dec 1;59(5):881-92
references.pmid: 2590944
references.citation: Development. 2006 Apr;133(8):1467-75
references.pmid: 16540511
references.citation: Nature. 1995 Jun 22;375(6533):654-8
references.pmid: 7791898
references.citation: Cell. 1991 Jul 12;66(1):37-50
references.pmid: 2070417
references.citation: EMBO J. 2004 Nov 24;23(23):4571-82
references.pmid: 15510215
references.citation: Curr Biol. 1994 Apr 1;4(4):289-300
references.pmid: 7922338
references.citation: Cell. 2006 Aug 11;126(3):583-96
references.pmid: 16887178
references.citation: Cell. 1991 Jul 12;66(1):23-35
references.pmid: 2070416
references.citation: Nature. 2004 Dec 23;432(7020):980-7
references.pmid: 15616552
references.citation: Cell. 1993 Oct 8;75(1):165-74
references.pmid: 7691414
references.citation: Development. 2007 May;134(10):1955-65
references.pmid: 17442699
references.citation: Mech Dev. 1999 Dec;89(1-2):35-42
references.pmid: 10559478
references.citation: Development. 2012 Jun;139(11):1987-96
references.pmid: 22513371
references.citation: Development. 2011 Nov;138(21):4661-71
references.pmid: 21989913
references.citation: Dev Biol. 2009 Apr 15;328(2):434-44
references.pmid: 19217894
references.citation: Curr Biol. 2002 Sep 3;12(17):1541-5
references.pmid: 12225672
references.citation: Mech Dev. 1996 Oct;59(2):105-13
references.pmid: 8951789
references.citation: Dev Cell. 2011 Feb 15;20(2):219-32
references.pmid: 21316589
references.citation: Development. 2002 Aug;129(15):3705-14
references.pmid: 12117819
references.citation: Development. 1994 Aug;120(8):2245-57
references.pmid: 7925025
references.citation: Curr Biol. 2002 Dec 10;12(23):1971-81
references.pmid: 12477385
references.citation: Development. 1993 Aug;118(4):1169-80
references.pmid: 8269846
references.citation: Curr Biol. 1997 May 1;7(5):326-37
references.pmid: 9115398
references.citation: Proc Natl Acad Sci U S A. 2009 Apr 14;106(15):6363-8
references.pmid: 19329489