Mannan, Ashraf U.

[["dc.bibliographiccitation.firstpage","788"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Biology of Reproduction"],["dc.bibliographiccitation.lastpage","796"],["dc.bibliographiccitation.volume","69"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Nayernia, K."],["dc.contributor.author","Mueller, C."],["dc.contributor.author","Burfeind, Peter"],["dc.contributor.author","Adham, Ibrahim M."],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T10:36:20Z"],["dc.date.available","2018-11-07T10:36:20Z"],["dc.date.issued","2003"],["dc.description.abstract","The testicular haploid expressed gene (Theg) encodes for a novel similar to42.0-kDa nuclear protein, which is specifically expressed in spermatid cells. Its expression is upregulated by some unknown factor(s) from Sertoli cells. To elucidate the function of Theg protein and its role in spermatogenesis, we disrupted the Theg locus in mouse by homologous recombination. For functional dissection of the domain structure of the Theg protein, two different knockout approaches were undertaken. In the first knockout mouse (Th14), the C-terminal region of the Theg protein (amino acids 137-376) was deleted. Both Th14(+/-) and Th14(-/-) mice from genetic backgrounds of C57BL/6J X 129X1/ SvJ hybrid and 129X1/SvJ inbred exhibited a normal phenotype and were fertile. The testes of Th14(-/-) mice were smaller than those of Th14(+/-) and Th14(+/+) mice; however, the testicular morphology and the properties of sperm, including morphology and motility, from Th14(-/-) mice were similar to those of Th14(+/-) and Th14(+/+) mice. These results demonstrate that the C-terminal region of Theg (amino acids 137-376) does not play an important role in progression of spermatogenesis. In the second knockout mouse (Th15), we deleted the N-terminal domain of the Theg protein, which resulted in complete loss of Theg transcripts. Both Th15(+/-) and Th15(-/-) mice from genetic backgrounds C57BL/6J x 129X1/SvJ hybrid, C3H/J congenic, and 129X1/SvJ inbred appeared normal and were fertile, with no gross abnormalities detected in testicular morphology or sperm properties. Our results from both knockout mouse model systems clearly illustrate that Theg is not essential for spermatogenesis in the mouse."],["dc.identifier.doi","10.1095/biolreprod.103.017400"],["dc.identifier.isi","000184989100007"],["dc.identifier.pmid","12748127"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/45299"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Soc Study Reproduction"],["dc.relation.issn","0006-3363"],["dc.title","Male mice lacking the theg (Testicular haploid expressed gene) protein undergo normal spermatogenesis and are fertile"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","229"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Neurogenetics"],["dc.bibliographiccitation.lastpage","238"],["dc.bibliographiccitation.volume","5"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Roussa, Eleni"],["dc.contributor.author","Kraus, Cornelia"],["dc.contributor.author","Rickmann, Michael"],["dc.contributor.author","Maenner, Joerg"],["dc.contributor.author","Nayernia, K."],["dc.contributor.author","Krieglstein, Kerstin"],["dc.contributor.author","Reis, A."],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T10:43:34Z"],["dc.date.available","2018-11-07T10:43:34Z"],["dc.date.issued","2004"],["dc.description.abstract","We report a novel spontaneous mutation named nax in mice, which exhibit delayed hair appearance and ataxia in a homozygote state. Histological analyses of nax brain revealed an overall impairment of the cerebellar cortex. The classical cortical cytoarchitecture was disrupted, the inner granule cell layer was not obvious, the Purkinje cells were not aligned as a Purkinje cell layer, and Bergmann glias did not span the molecular layer. Furthermore, histological analyses of skin showed that the hair follicles were also abnormal. We mapped the nax locus between marker D2Mit158 and D2Mit100 within a region of 800 kb in the middle of chromosome 2 and identified a missense mutation (Gly244Glu) in Acp2, a lysosomal monoesterase. The Glu244 mutation does not affect the stability of the Acp2 transcript, however it renders the enzyme inactive. Ultrastructural analysis of nax cerebellum showed lysosomal storage bodies in nucleated cells, suggesting progressive degeneration as the underlying mechanism. Identification of Acp2 as the gene mutated in nax mice provides a valuable model system for studying the role of Acp2 in cerebellum and skin homeostasis."],["dc.identifier.doi","10.1007/s10048-004-0197-9"],["dc.identifier.isi","000226285100005"],["dc.identifier.pmid","15503243"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/47086"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1364-6745"],["dc.title","Mutation in the gene encoding lysosomal acid phosphatase (Acp2) causes cerebellum and skin malformation in mouse"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","93"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Neurogenetics"],["dc.bibliographiccitation.lastpage","103"],["dc.bibliographiccitation.volume","7"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Boehm, J."],["dc.contributor.author","Sauter, Simone M."],["dc.contributor.author","Rauber, A."],["dc.contributor.author","Byrne, P. C."],["dc.contributor.author","Neesen, J."],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T09:55:10Z"],["dc.date.available","2018-11-07T09:55:10Z"],["dc.date.issued","2006"],["dc.description.abstract","Spastin, an ATPase belonging to the AAA family of proteins is most commonly mutated in autosomal dominant hereditary spastic paraplegias (HSP). Spastin is a multifaceted protein with versatile role in cellular events, principally involved in microtubule dynamics. To gain further insight into the molecular function of spastin, we used the yeast two-hybrid approach to identify novel interacting partners of spastin. Using spastin as bait, we identified reticulon 1 (RTN1) and reticulon 3 (RTN3) as potential spastin interacting proteins. RTN1 and RTN3 belong to the reticulon (RTN) gene family, which are primarily expressed in the endoplasmic reticulum. Moreover, RTN1 is known to play a role in vesicular transport processes. Using in vitro and in vivo immunoprecipitation experiments, we were able to demonstrate that RTN1 interacts specifically with spastin. Intracellular distribution studies using immunostaining and overexpression of epitope-tagged protein revealed an obvious colocalization of spastin and RTN1 in discrete vesicles in the cytoplasm. Spastin mediates its interaction with RTN1 through its N-terminal region containing a microtubule-interacting and trafficking domain. It is interesting to note that the aberrant intracellular distribution of a truncated spastin protein was rescued by coexpression with RTN1, which highlights the physiological significance of this interaction. Our findings strengthen the hypothesis that disruption of intracellular vesicular transport processes could cause HSP. It is interesting to note that RTN1 is localized to 14q23.1 where SPG15 locus was mapped. Therefore, we considered RTN1 as a candidate gene for the SPG15 locus, but our mutational analysis possibly excludes RTN1 as causative gene."],["dc.identifier.doi","10.1007/s10048-006-0034-4"],["dc.identifier.isi","000237325600003"],["dc.identifier.pmid","16602018"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/36690"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Springer"],["dc.relation.issn","1364-6745"],["dc.title","Spastin, the most commonly mutated protein in hereditary spastic paraplegia interacts with reticulon 1 an endoplasmic reticulum protein"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","351"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","The American Journal of Human Genetics"],["dc.bibliographiccitation.lastpage","357"],["dc.bibliographiccitation.volume","79"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Krawen, Philip"],["dc.contributor.author","Sauter, Simone M."],["dc.contributor.author","Boehm, Johann"],["dc.contributor.author","Chronowska, Agnieszka"],["dc.contributor.author","Paulus, Walter J."],["dc.contributor.author","Neesen, Juergen"],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T09:26:29Z"],["dc.date.available","2018-11-07T09:26:29Z"],["dc.date.issued","2006"],["dc.description.abstract","Spastin, the most commonly mutated protein in the autosomal dominant form of hereditary spastic paraplegia (ADHSP) has been suggested to be involved in vesicular cargo trafficking; however, a comprehensive function of spastin has not yet been elucidated. To characterize the molecular function of spastin, we used the yeast two-hybrid approach to identify new interacting partners of spastin. Here, we report ZFYVE27, a novel member of the FYVE-finger family of proteins, as a specific spastin-binding protein, and we validate the interaction by both in vivo coimmunoprecipitation and colocalization experiments in mammalian cells. More importantly, we report a German family with AD-HSP in which ZFYVE27 (SPG33) is mutated; furthermore, we demonstrate that the mutated ZFYVE27 protein shows an aberrant intracellular pattern in its tubular structure and that its interaction with spastin is severely affected. We postulate that this specific mutation in ZFYVE27 affects neuronal intracellular trafficking in the corticospinal tract, which is consistent with the pathology of HSP."],["dc.identifier.doi","10.1086/504927"],["dc.identifier.isi","239040400016"],["dc.identifier.pmid","16826525"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/30313"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Univ Chicago Press"],["dc.relation.issn","0002-9297"],["dc.title","ZFYVE27 (SPG33), a novel spastin-binding protein, is mutated in hereditary spastic paraplegia"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","431"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Molecular Reproduction and Development"],["dc.bibliographiccitation.lastpage","438"],["dc.bibliographiccitation.volume","66"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Nica, G."],["dc.contributor.author","Nayernia, K."],["dc.contributor.author","Mueller, C."],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T10:34:29Z"],["dc.date.available","2018-11-07T10:34:29Z"],["dc.date.issued","2003"],["dc.description.abstract","The murine calgizzarin like gene (Cal) encodes for a calcium binding protein, which belongs to the S100 family of EF-hand proteins. It is specifically expressed in Sertoli cells in the testis and its expression is down-regulated by unknown factor(s) from spermatocytes/spermatids. In this paper, we show by transfection of a fusion protein of green fluorescent protein and Cal protein into NIH3T3 cells, that the expression of Cal is restricted only in the cytoplasm of the cell. A differentially regulated cytoplasmic expression of the Cal in Sertoli cells during mouse development suggests that Cal might play an important role during spermatogenesis. In order to elucidate the function of the Cal protein in the spermatogenesis, we disrupted the Cal locus in mouse by homologous recombination. In our knockout mouse, we deleted exon 2 and exon 3 of the Cal gene and replaced them with a neomycin cassette, which resulted in a complete loss of the Cal transcript. Male and female Cal4(+/-) and Cal4(-/-) mice from genetic backgrounds C57BL/6J x 129X1/SvJ hybrid and 129X1/SvJ inbred exhibited normal phenotype and were fertile. An intensive phenotypic analysis showed no gross abnormalities in testis morphology. The lack of the Cal protein also does not affect the parameters of sperm, as they are able to fertilize the oocytes in a competent manner, which is comparable to wild-type sperm. Collectively our results demonstrate that Cal is a nonessential protein and it does not play an important role in mouse spermatogenesis or in process of fertilization. (C) 2003 Wiley-Liss, Inc."],["dc.identifier.doi","10.1002/mrd.10367"],["dc.identifier.isi","000186391400012"],["dc.identifier.pmid","14579419"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/44884"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wiley-liss"],["dc.relation.issn","1040-452X"],["dc.title","Calgizarrin like gene (Cal) deficient mice undergo normal spermatogenesis"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","171"],["dc.bibliographiccitation.issue","1-4"],["dc.bibliographiccitation.journal","CYTOGENETICS AND CELL GENETICS"],["dc.bibliographiccitation.lastpage","179"],["dc.bibliographiccitation.volume","91"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Lucke, K."],["dc.contributor.author","Dixkens, C."],["dc.contributor.author","Neesen, J."],["dc.contributor.author","Kamper, M."],["dc.contributor.author","Engel, Wolfgang"],["dc.contributor.author","Burfeind, Peter"],["dc.date.accessioned","2018-11-07T11:03:03Z"],["dc.date.available","2018-11-07T11:03:03Z"],["dc.date.issued","2000"],["dc.description.abstract","We have previously isolated and characterized the mouse Testicular Haploid Expressed Gene (Theg) that is specifically expressed in haploid germ cells. We now describe the molecular cloning and characterization of the human homologue (THEG) of mouse Theg. Expression studies by using both dot blot and Northern blot techniques revealed that human THEG is expressed specifically in the testis. Additionally, we found two alternatively spliced transcripts (THEG major and THEG minor) for THEG by using reverse transcription-polymerase chain reaction on human testicular RNA. Sequence analysis of these PCR products demonstrated that the smaller transcript (THEG minor) lacks 72 bp which was also observed for the mouse Theg. We have isolated the cDNAs of human THEG major and THEG minor, containing the complete open reading frames, which encode putative nuclear proteins of 379 amino acids and 355 amino acids, respectively. Database searches identified two genomic clones on chromosome 19 harboring the human THEG gene, which is approximately 14 kb pairs in size, contains eight exons, and comparison of the two cDNA sequences with the genomic sequence indicated that the smaller transcript lacks exon 3. Furthermore, we assigned the human THEG gene (THEG) to human chromosome 19ptel-->p13 by fluorescence in situ hybridization. Moreover, we detected mouse THEG protein prominently in the nucleus of round spermatids by using an antibody against THEG on both testicular sections and cellular suspensions. Additionally, the subcellular localization of mouse THEG was confirmed by a green fluorescent protein (GFP) fusion protein of mouse THEG which was found mainly in the nucleus of transfected NIH3T3 cells. These data suggest that both human and mouse THEG are specifically expressed in the nucleus of haploid male germ cells and are involved in the regulation of nuclear functions. Copyright (C),2001 S.Karger AG, Basel."],["dc.identifier.doi","10.1159/000056840"],["dc.identifier.isi","000166856000034"],["dc.identifier.pmid","11173852"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/51528"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Karger"],["dc.relation.issn","0301-0171"],["dc.title","Alternative splicing, chromosome assignment and subcellular localization of the testicular haploid expressed gene (THEG)"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.journal","European Journal of Human Genetics"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Mannan, Ashraf U."],["dc.contributor.author","Nica, G."],["dc.contributor.author","Nayernia, K."],["dc.contributor.author","Engel, Wolfgang"],["dc.date.accessioned","2018-11-07T10:30:08Z"],["dc.date.available","2018-11-07T10:30:08Z"],["dc.date.issued","2002"],["dc.format.extent","165"],["dc.identifier.isi","000187166100521"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/43798"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Nature Publishing Group"],["dc.publisher.place","London"],["dc.relation.conference","European-Society-of-Human-Genetics European Human Genetics Conference in Conjuction With European Meeting on Psychosocial Aspects of Genetics"],["dc.relation.eventlocation","STRASBOURG, FRANCE"],["dc.relation.issn","1018-4813"],["dc.title","Sertoli cell-germ cell interaction: Functional analysis of murine calgizzarin gene."],["dc.type","conference_abstract"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]