Navigation Links
Telling axons where to go - and grow

In a recent study, Dr. Ingolf Bach and colleagues from the University of Massachusetts Medical School, Worcester and the University of Hamburg (Germany) describe a novel role for the ubiquitin/proteosome protein degradation pathway in the regulation of local actin dynamics in neurons.

The authors are able to show that the ubiquitin ligase Rnf6 polyubiquitinates the kinase LIMK1, targeting it for proteosomal degradation in the growth cones of hippocampal neurons. LIMK1 regulates the dynamics of the actin cytoskeleton primarily via phosphorylation of the actin depolymerization factors ADF/cofilin, with important consequences for cell morphology, cell motility, and the development of neuronal projections. Changes in LIMK1 concentration have an impact in neuronal growth cone actin dynamics and axon formation.

The authors focus on the RING finger protein Rnf6 due to its similarity to the previously identified protein RLIM, which has been shown to bind to nuclear LIM domains and critically regulate the biological activity of LIM-HD transcription factors. The authors find high levels of Rnf6 protein in axonal projections of motor neurons and dorsal root ganglia neurons in mouse embryos at a time in which projections are actively developing, suggesting a role of this protein in the development of these neurons. They are able to show that this is indeed the case by RNAi-mediated knock-down of Rnf6 in primary hippocampal neurons, which stimulate axon outgrowth, and by over-expression of Rnf6 that results in a significant decrease in axon length.

Finding that Rnf6 targets LIMK1 for degradation finally closes this circle of regulation, providing the link between actin dynamics, axonal growth and Rnf6. Importantly, the authors are able to show that changes in axon outgrowth induced by changes in levels of Rnf6 can be restored by compensatory changes in LIMK1 expression, thereby giving Rnf6 a central role in controlling actin dynamics in subcellula r structures. Because LIMK1 has been implicated in biological processes such as metastasis and invasion of cancer, Dr. Bach points out that "�these results indicate that Rnf6 not only plays an important role in coordinating neuronal development but may be also involved in oncogenesis."


Source:Cold Spring Harbor Laboratory

Related biology news :

1. Discovery of an American salamander where it shouldnt be: Korea
2. Vaccine targets tumors where they live
3. Unraveling where chimp and human brains diverge
4. Plant studies reveal how, where seeds store iron
5. Plant studies reveal how, where seeds store iron
6. Why do oysters choose to live where they could be eaten?
7. At long last, scientists figure out how plants grow
8. Dopamine used to prompt nerve tissue to regrow
Post Your Comments:

(Date:5/16/2016)... May 16, 2016   EyeLock LLC , a ... the opening of an IoT Center of Excellence in ... expand the development of embedded iris biometric applications. ... of convenience and security with unmatched biometric accuracy, making ... aside from DNA. EyeLock,s platform uses video technology to ...
(Date:5/9/2016)... , UAE, May 9, 2016 ... it comes to expanding freedom for high net worth ... Even in today,s globally connected world, there is still ... system could ever duplicate sealing your deal with a ... second passports by taking advantage of citizenship via investment ...
(Date:4/28/2016)... FRANCISCO and BANGALORE, India , ... of EdgeVerve Systems, a product subsidiary of Infosys (NYSE: ... provider, today announced a global partnership that will ... way to use mobile banking and payment services. ... is a key innovation area for financial services, but it ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... ... June 23, 2016 , ... Charm ... Mold) microbial test has received AOAC Research Institute approval 061601. , “This is ... last year,” stated Bob Salter, Vice President of Regulatory and Industrial Affairs. “The ...
(Date:6/23/2016)... June, 23, 2016  The Biodesign Challenge (BDC), a ... ways to harness living systems and biotechnology, announced its ... in New York City . ... students, showcased projects at MoMA,s Celeste Bartos Theater during ... , MoMA,s senior curator of architecture and design, and ...
(Date:6/23/2016)... ... , ... Supplyframe, the Industry Network for electronics hardware design ... Located in Pasadena, Calif., the Design Lab’s mission is to bring together inventors ... and brought to market. , The Design Lab is Supplyframe’s physical representation of ...
(Date:6/23/2016)... ... June 23, 2016 , ... In a new case report ... detail how a patient who developed lymphedema after being treated for breast cancer benefitted ... change the paradigm for dealing with this debilitating, frequent side effect of cancer treatment. ...
Breaking Biology Technology: