Abstract：
:Null-mutation in Drosophila importin-alpha2, such as the deficiency imp-alpha2(D14), causes recessive female sterility with the formation of dumpless eggs. In imp-alpha2(D14) the transfer of nurse cell components to the oocyte is interrupted and the Kelch protein, an oligomeric ring canal actin organizer, is normally produced but fails to associate with the ring canals resulting in their occlusion. To define domains regulating Kelch deposition on ring canals we performed site-directed mutagenesis on protein binding domains and putative phosphorylation sites of Imp-alpha2. Phenotypic analysis of the mutant transgenes in imp-alpha2(D14) revealed that mutations affecting the Imp-beta binding-domain, the dimerization domain, and specific serine residues of putative phosphorylation sites led to a normal or nearly normal oogenesis but arrested early embryonic development, whereas mutations in the nuclear localization signal (NLS) and CAS/exportin binding domains resulted in ring canal occlusion and a drastic nuclear accumulation of the mutant proteins. Deletion of the Imp-beta binding domain also gave rise to a nuclear localization of the mutant protein, which partially retained its function in ring canal assembly. Thus, we propose that mutations in NLS and CAS binding domains affect the deposition of Kelch onto the ring canals and prevent the association of Imp-alpha2 with a negative regulator of Kelch function.
journal_name
J Struct Bioljournal_title
Journal of structural biologyauthors
Gorjánácz M,Török I,Pomozi I,Garab G,Szlanka T,Kiss I,Mechler BMdoi
10.1016/j.jsb.2005.12.007keywords:
subject
Has Abstractpub_date
2006-04-01 00:00:00pages
27-41issue
1eissn
1047-8477issn
1095-8657pii
S1047-8477(05)00286-8journal_volume
154pub_type
杂志文章abstract：:In arthropods the cuticle forms an exoskeleton with its physical and chemical properties adapted to functions of distinct skeletal elements. The cuticle of the partes incisivae (PI) in mandibles of terrestrial isopods is a composite of chitin-protein fibrils/fibres and minerals. It consists of an unmineralized tip, a ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2015.03.007
更新日期：2015-05-01 00:00:00
abstract：:Like in most Crustacea, the cuticle of terrestrial isopods is hardened by a calcareous mineral phase. This rigid cuticle is frequently shed during a process called moulting. To reduce calcium loss, Porcellio scaber eats the shed cuticle, the exuviae, and absorb the calcium from it through large tubular diverticula of ...
journal_title：Journal of structural biology
pub_type： 杂志文章
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journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2007.09.015
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abstract：:Seeding has been critical for obtaining diffraction-quality crystals for many structures. In this article, applications and recommendations for seeding are presented based on examples from our laboratory and other groups. The implementation of seeding in high-throughput crystallization, robotics, and other emerging te...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1016/s1047-8477(03)00039-x
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journal_title：Journal of structural biology
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journal_title：Journal of structural biology
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2004.03.002
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1998.4999
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journal_title：Journal of structural biology
pub_type： 杂志文章,评审
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1996.0084
更新日期：1996-11-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2018.02.003
更新日期：2019-04-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3851
更新日期：1997-03-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1999.4087
更新日期：1999-06-01 00:00:00
abstract：:In fishes, like in amphibians, it is well established that variations in rRNA activity occur during oogenesis. Contrary to amphibians, however, little is known about the ultrastructural changes of the nucleolus during fish oogenesis. Evolution of the nucleolus has been followed during oogenesis in the teleost fish Bar...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.07.006
更新日期：2005-10-01 00:00:00
abstract：:Overproduction and crystallization of Bacillus stearothermophilus ribosomal protein S7 (BstS7), a primary 16S rRNA binding protein and also a translational repressor protein, have been performed to analyze its three-dimensional structure by X-ray crystallography. Ribosomal protein BstS7 was expressed in the cytoplasmi...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3907
更新日期：1997-10-01 00:00:00
abstract：:The structures of many helical protein filaments can be derived from electron micrographs of their suspensions in thin films of vitrified aqueous solutions. The most successful and generally-applicable approach treats short segments of these filaments as independent "single particles", yielding near-atomic resolution ...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2014.03.012
更新日期：2014-05-01 00:00:00
abstract：:Zn-alpha2-glycoprotein (ZAG) is a 41 kDa soluble protein that is present in most bodily fluids. The previously reported 2.8 A crystal structure of ZAG isolated from human serum demonstrated the structural similarity between ZAG and class I major histocompatibility complex (MHC) molecules and revealed a non-peptidic li...
journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2004.04.009
更新日期：2004-11-01 00:00:00
abstract：:Helicases are proteins that use the energy of ATP hydrolysis to open double-stranded DNA, RNA, or RNA-DNA hybrids into two single strands. Based upon sequence analysis, at least 12 helicases exist in Escherichia coli. We know that these proteins play important roles in DNA replication, recombination, repair, and trans...
journal_title：Journal of structural biology
pub_type： 杂志文章,评审
doi：10.1006/jsbi.1998.4050
更新日期：1998-12-15 00:00:00
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journal_title：Journal of structural biology
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doi：10.1016/j.jsb.2017.09.007
更新日期：2017-11-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
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更新日期：2018-06-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1016/j.jsb.2005.03.010
更新日期：2005-07-01 00:00:00
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journal_title：Journal of structural biology
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journal_title：Journal of structural biology
pub_type： 杂志文章
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更新日期：2009-12-01 00:00:00
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journal_title：Journal of structural biology
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更新日期：2009-09-01 00:00:00
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journal_title：Journal of structural biology
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更新日期：2014-09-01 00:00:00
abstract：:The phycobilisome photosynthetic antenna complex, found in cyanobacteria and red-algae, interacts with proteins expressed specifically to deal with different forms of physiological stress. Under conditions of nutrient starvation, the NblA protein is required for the process that leads to phycobilisome degradation and ...
journal_title：Journal of structural biology
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更新日期：2007-04-01 00:00:00
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journal_title：Journal of structural biology
pub_type： 杂志文章
doi：10.1006/jsbi.1997.3948
更新日期：1998-01-01 00:00:00
abstract：:Biophysical cues such as substrate modulus have been shown to influence a variety of cell behaviors. We have determined the elastic modulus of the anterior basement membrane and Descemet's membrane of the human cornea with atomic force microscopy (AFM). A spherical probe was used with a radius approximating that of a ...
journal_title：Journal of structural biology
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更新日期：2009-07-01 00:00:00
