You are viewing an incomplete version of our website. Please click to reload the website as full version.

Microtubule Dynamics

Mikrotubuli sind hochdynamische strukturelle und funktionelle intrazelluläre „Autobahnen”. Der Begriff Zytoskelett (Cytoskelett) ruft das Bild einer starren, unveränderlichen und permanenten Struktur hervor. In Wirklichkeit ist das Zytoskelett allerdings ein hochdynamisches miteinander verbundenes Netzwerk, das aus drei unterschiedlichen Hauptkomponenten besteht: Mikrotubuli (polymerisierte Tubulin-Dimere), Mikrofilamente (polymerisiertes Aktin) und Intermediärfilamente. Mikrotubuli sind die größten Komponenten des Zytoskeletts. Sie spielen bei nahezu allen zellulären Prozessen eine Rolle und verleihen einer ansonsten amorphen Zelle strukturelle Stabilität und Form. Sie sind die Hauptkomponenten in einer vernetzten intrazellulären „Autobahn”, wodurch jede Art von zellulärer Fracht über ein belebtes Netzwerk molekularer Motorproteine geleitet werden kann. Während der Mitose liefert die Kontraktion der Mikrotubuli, die sich auf eine der beiden Mitosespindeln konzentriert, die notwendige Kraft, um die Chromosomen zu teilen.

Die sich ständig ändernden zelluläre Mikroumgebung erfordert Anpassungsfähigkeit, insbesondere bei der Entwicklung. Mikrotubuli und andere Zytoskelettkomponenten erleichtern diese Anpassungsfähigkeit aufgrund ihrer polymeren Struktur. Die Grundeinheit des Mikrotubulus ist ein Tubulin-Dimer, der sich aus einer alpha-Tubulin-Untereinheit und einer entsprechenden beta-Tubulin-Untereinheit zusammensetzt. Diese Dimere polymerisieren, um eine hohle, röhrenförmige Struktur von etwa 24 nm Breite zu bilden. Der natürliche Zustand eines nicht modifizierten Tubulins verändert sich permanent mit einer nahezu gleichen Polymerisations- und Depolymerisationsgeschwindigkeit.

Verschiedene, häufig vorkommende GTPase-Familien wie Rac und Rho fördern indirekt den Aufbau von Mikrotubuli, indem sie den GDP/GTP-Austausch über die Tubulin-Dimere erleichtern. Andere Mikrotubuli-Stabilisatoren gehen direkter vor. Mikrotubuli-assoziierte Proteine wie MAP1, MAP2, MAP4 oder MAPtau binden polymerisierte Mikrotubuli und stabilisieren die polymerisierte Form, indem sie den Aufbau und Wachstum der Mikrotubuli fördern. Die meisten MAPs werden durch Phosphorylierung aktiviert, und MAPK (MAP-Kinase)-Phosphorylierungskaskaden bieten während des Aufbaus von Mikrotubuli eine zusätzliche Kontrollinstanz. Umgekehrt haben Zellen verschiedene Möglichkeiten, den Abbau von Mikrotubuli zu regulieren. Direkte Methoden zur Förderung des Abbaus umfassen Komponenten wie Stathmin, das α- und β-Tubulin-Dimere bindet und sie an einer Polymerisation hindert. Mikrotubuli-trennende Enzyme wie Katanin können Mikrotubuli in der Mitte ihrer Struktur brechen, während hingegen Kinsesin I Familienmitglieder, wie beispielsweise KIF2, entlang der Mikrotubuli wandern und ein „Ausfransen“ und eine Depolymerisation fördern.

Microtubule-associated proteins

CLASP1 (Cytoplasmic Linker Associated Protein 1):

CLASPs, such as CLASP1, are nonmotor microtubule-associated proteins that interact with CLIPs (e.g., CLIP170\; MIM 179838). CLASP1 is involved in the regulation of microtubule dynamics at the kinetochore and throughout the spindle (Maiato et al., 2003 [PubMed 12837247]).[supplied by OMIM, Mar 2008].   More...

MAPT (Microtubule-Associated Protein tau):

This gene encodes the microtubule-associated protein tau (MAPT) whose transcript undergoes complex, regulated alternative splicing, giving rise to several mRNA species. MAPT transcripts are differentially expressed in the nervous system, depending on stage of neuronal maturation and neuron type. MAPT gene mutations have been associated with several neurodegenerative disorders such as...   More...
Antigene in dieser Kategorie:
CLIP1 (CAP-GLY Domain Containing Linker Protein 1): CLIP1 Antikörper CLIP1 ELISA Kits  
CLIP2 (CAP-GLY Domain Containing Linker Protein 2): CLIP2 Antikörper CLIP2 ELISA Kits CLIP2 Proteine
CLASP2 (Cytoplasmic Linker Associated Protein 2): CLASP2 Antikörper CLASP2 ELISA Kits CLASP2 Proteine
MAP1A (Microtubule-Associated Protein 1A): MAP1A Antikörper MAP1A ELISA Kits MAP1A Proteine
MAP1B (Microtubule-Associated Protein 1B): MAP1B Antikörper MAP1B ELISA Kits  
MAP4 (Microtubule-Associated Protein 4): MAP4 Antikörper MAP4 ELISA Kits MAP4 Proteine

Tubulins

Tuba1a - TUBA1A

Tubulin is the major constituent of microtubules. It binds two moles of GTP, one at an exchangeable site on the beta chain and one at a non-exchangeable site on the alpha-chain.   More...

TUBB (Tubulin, beta):

beta 5-tubulin\; polymerizes to form microtubules\; member of a family of structural proteins [RGD, Feb 2006].   More...

TUBA4A (Tubulin, alpha 4a):

Microtubules of the eukaryotic cytoskeleton perform essential and diverse functions and are composed of a heterodimer of alpha and beta tubulin. The genes encoding these microtubule constituents are part of the tubulin superfamily, which is composed of six distinct families. Genes from the alpha, beta and gamma tubulin families are found in all eukaryotes. The alpha and beta tubulins represent...   More...

TUBE1 (Tubulin, epsilon 1):

This gene encodes a member of the tubulin superfamily. This protein localizes to the centriolar sub-distal appendages that are associated with the older of the two centrioles after centrosome duplication. This protein plays a central role in organization of the microtubules during centriole duplication. A pseudogene of this gene is found on chromosome 5.[provided by RefSeq, Jan 2009].   More...
Antigene in dieser Kategorie:
TUBA1 - alpha Tubulin: TUBA1 Antikörper    
LOC732582 - Tubulin A: LOC732582 Antikörper    
TUBA1B (Tubulin, alpha 1B): TUBA1B Antikörper TUBA1B ELISA Kits TUBA1B Proteine
TUBA1C (Tubulin, alpha 1c): TUBA1C Antikörper TUBA1C ELISA Kits TUBA1C Proteine
TUBA3E (Tubulin, alpha 3e): TUBA3E Antikörper   TUBA3E Proteine
TUBA8 (Tubulin, alpha 8): TUBA8 Antikörper TUBA8 ELISA Kits TUBA8 Proteine
TUBA3C (Tubulin, Alpha, 3C): TUBA3C Antikörper TUBA3C ELISA Kits TUBA3C Proteine
TUBB1 (Tubulin, beta 1): TUBB1 Antikörper TUBB1 ELISA Kits TUBB1 Proteine
TUBB2A (Tubulin, beta 2A): TUBB2A Antikörper TUBB2A ELISA Kits TUBB2A Proteine
TUBB2B (Tubulin, beta 2B): TUBB2B Antikörper TUBB2B ELISA Kits TUBB2B Proteine
TUBb6 (Tubulin, beta 6): TUBb6 Antikörper TUBb6 ELISA Kits TUBb6 Proteine
TUBB2C (Tubulin, Beta, 2C): TUBB2C Antikörper TUBB2C ELISA Kits TUBB2C Proteine
TUBB3 (Tubulin, Beta, 3): TUBB3 Antikörper TUBB3 ELISA Kits TUBB3 Proteine
TUBB5 (Tubulin, Beta, 5): TUBB5 Antikörper TUBB5 ELISA Kits TUBB5 Proteine
TUBD1 (Tubulin, delta 1): TUBD1 Antikörper TUBD1 ELISA Kits TUBD1 Proteine
TUBG1 (Tubulin, gamma 1): TUBG1 Antikörper TUBG1 ELISA Kits TUBG1 Proteine
TUBG2 (Tubulin, gamma 2): TUBG2 Antikörper TUBG2 ELISA Kits TUBG2 Proteine

Stabilization/Assembly

CLIP1 (CAP-GLY Domain Containing Linker Protein 1):

The protein encoded by this gene links endocytic vesicles to microtubules. This gene is highly expressed in Reed-Sternberg cells of Hodgkin disease. Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2011].   More...

CDC42 (Cell Division Cycle 42 (GTP Binding Protein, 25kDa)):

The protein encoded by this gene is a small GTPase of the Rho-subfamily, which regulates signaling pathways that control diverse cellular functions including cell morphology, migration, endocytosis and cell cycle progression. This protein is highly similar to Saccharomyces cerevisiae Cdc 42, and is able to complement the yeast cdc42-1 mutant. The product of oncogene Dbl was reported to...   More...

CLASP1 (Cytoplasmic Linker Associated Protein 1):

CLASPs, such as CLASP1, are nonmotor microtubule-associated proteins that interact with CLIPs (e.g., CLIP170\; MIM 179838). CLASP1 is involved in the regulation of microtubule dynamics at the kinetochore and throughout the spindle (Maiato et al., 2003 [PubMed 12837247]).[supplied by OMIM, Mar 2008].   More...
Antigene in dieser Kategorie:
CLIP2 (CAP-GLY Domain Containing Linker Protein 2): CLIP2 Antikörper CLIP2 ELISA Kits CLIP2 Proteine
CLASP2 (Cytoplasmic Linker Associated Protein 2): CLASP2 Antikörper CLASP2 ELISA Kits CLASP2 Proteine
MAP1A (Microtubule-Associated Protein 1A): MAP1A Antikörper MAP1A ELISA Kits MAP1A Proteine
MAP1B (Microtubule-Associated Protein 1B): MAP1B Antikörper MAP1B ELISA Kits  
MAP4 (Microtubule-Associated Protein 4): MAP4 Antikörper MAP4 ELISA Kits MAP4 Proteine
MAPT (Microtubule-Associated Protein tau): MAPT Antikörper MAPT ELISA Kits MAPT Proteine
RHOA (Ras Homolog Gene Family, Member A): RHOA Antikörper RHOA ELISA Kits RHOA Proteine
ROCK1 (rho-Associated, Coiled-Coil Containing Protein Kinase 1): ROCK1 Antikörper ROCK1 ELISA Kits ROCK1 Proteine
ROCK2 (rho-Associated, Coiled-Coil Containing Protein Kinase 2): ROCK2 Antikörper ROCK2 ELISA Kits ROCK2 Proteine

Destabilization/Disassembly

FIGNL1 (Fidgetin-Like 1):

May regulate osteoblast proliferation and differentiation (By similarity).   More...

KIF2C (Kinesin Family Member 2C):

The protein encoded by this gene is a member of kinesin-like protein family. Proteins of this family are microtubule-dependent molecular motors that transport organelles within cells and move chromosomes during cell division. This protein is important for anaphase chromosome segregation and may be required to coordinate the onset of sister centromere separation. [provided by RefSeq, Jul 2008].   More...

vps4b - VPS4B

The protein encoded by this gene is a member of the AAA protein family (ATPases associated with diverse cellular activities), and is the homolog of the yeast Vps4 protein. In humans, two paralogs of the yeast protein have been identified. The former share a high degree of aa sequence similarity with each other, and also with yeast Vps4 and mouse Skd1 proteins. Mouse Skd1 (suppressor of K+...   More...
Antigene in dieser Kategorie:
EML2 (Echinoderm Microtubule Associated Protein Like 2): EML2 Antikörper EML2 ELISA Kits EML2 Proteine
KATNA1 (Katanin P60 (ATPase Containing) Subunit A 1): KATNA1 Antikörper KATNA1 ELISA Kits KATNA1 Proteine
KATNB1 (Katanin P80 (WD Repeat Containing) Subunit B 1): KATNB1 Antikörper KATNB1 ELISA Kits KATNB1 Proteine
KIF2B (Kinesin Family Member 2B): KIF2B Antikörper KIF2B ELISA Kits KIF2B Proteine
KIF2A - Kinesin Heavy Chain Member 2A: KIF2A Antikörper KIF2A ELISA Kits KIF2A Proteine
SPAST - Spastin: SPAST Antikörper SPAST ELISA Kits SPAST Proteine
STMN1 - Stathmin 1: STMN1 Antikörper STMN1 ELISA Kits STMN1 Proteine
VPS4A (Vacuolar Protein Sorting 4 Homolog A (S. Cerevisiae)): VPS4A Antikörper VPS4A ELISA Kits VPS4A Proteine