educratsweb logo


Scientists from Raman Research Institute (RRI), an autonomous institute under the Department of Science &Technology along with IISER Pune and Paris Diderot University, have found out that spectrin, which are flexible rod-shaped molecules present in axons, act as ‘shock absorbers’ to protect axons from stretch-induced damage.

 

The study can help in understanding and treatment of concussion from head injuries as well as stretch-induced nerve injuries.

 

Axons are long tubular extensions of nerve cells that transmit electrical signals across long distances and can be up to a meter long in the case of humans. At such lengths, they are subjected to large stretch deformations during limb or other bodily movements. Axons in the brain too undergo significant deformations, even during normal activities like jumping (the human brain is as soft and wobbly as edible jelly).

 

Probing into what special strategies axons adopt to protect themselves from damage during such stretch deformations, the scientists zeroed in on the molecule spectrin, a cytoskeletal protein.

 

In their research published in journal eLife, with Dr. Sushil Dubey as the lead author, Prof. Pramod Pullarkatand his team from RRI showed that neuronal cells may have evolved a clever strategy using an etched optical fiber attached to a piezo drive as a force-sensing cantilever to stretch live axons and to measure the resultant tension. Piezo drives attached to optical fiber is used to stretch on axons where optical fiber acts as a force-sensing cantilever. The resulting tension measured along the axon comes from the axonal cytoskeleton (consisting of biopolymers), of which spectrin is a part.

 

The RRI team took clues from a recent discovery, which showed that axons have a periodic scaffold consisting of longitudinally arranged long spectrin protein molecules. The function of this skeleton was a puzzle. The experiments by the RRI team on axons that are biochemically or genetically modified to disrupt specific cytoskeletal components revealed that the spectrin scaffold has a prominent mechanical role.

 

Earlier single-molecule experiments had shown that spectrin molecules contain several folded regions which can unfold when the protein is stretched and refold when released, thus acting as molecular bellows. By comparing detailed tension measurements on axons with a mathematical model that describes such a mechanism, the RRI team showed that this process helps axons to buffer tension and dissipate excess elastic energy. Unlike a linear spring, where the tension increases proportionally with stretch, axonal tension exhibits a plateau-like region where tension is only weakly dependent on stretch, due to the unfolding process. This suggests that spectrins can act as axonal ‘shock absorbers’ to protect axons from stretch-induced damage.

 

The brain undergoes significant shear deformations (up to 5% of strain) even under normal activities such as jumping. In contact sports, brain concussion occurs and is a leading cause of injuries. This study will have significant implications to our understanding of concussion that result from head impacts as well as stretch-induced nerve injuries.

 

Fig: Probing axonal mechanics using home-built Micro-Extension Rheometer reveals strain-softening in axons that protect neurons from damage via reversibly unfolding of spectrin repeated units.

(A) A schematic of the home-developed force apparatus that uses an etched optical fiber as a cantilever to stretch axons and to sense force.

(B) Typical force and tension response of an axon to increasing strain explored using successive strain steps. The inset shows the images of the axon before and after stretch.

 

(C) Typical structure of a neuronal cell and its cytoskeleton. The outermost scaffold of the axonal cytoskeleton has an array of periodically spaced rings composed of F-actin filaments.

The actin rings are interconnected by spectrin tetramers, which are aligned along the axonal axis.

 

[Publication: https://elifesciences.org/articles/51772

For more details contact Dr. Sushil Dubey (dubeys@rri.res.in,+917760581324)]

Molecular shock absorbers buffer axonal tension of nerve cells
Contents shared By educratsweb.com

if you have any information regarding Job, Study Material or any other information related to career. you can Post your article on our website. Click here to Register & Share your contents.
For Advertisment or any query email us at educratsweb@gmail.com

RELATED POST
List of Holidays - 2019: Gazetted Leave - Central Government Employees Calendar
1 Simba Movie trailer Download | Talented India 
2 Mann Ki Baat 2.0 | Programme on All India Radio (30.06.2019)
3 आरबीआई दे रहा नौकरी का सुनहरा मौका
4
5 शिवराज का मप्र की राजनीति से अध्याय खत्म
6 PhonePe Scratch Card Offers - Chance to Earn Rs. 1000 Per Money Transfer
7 IPL auction: Learn base price of players
8 CG Vyapam Recruitment 2019 : कई पदों पर भर्तियां
9 राष्ट्रीय स्वास्थ्य मिशन उत्तर प्रदेश भर्ती 2020
10 हाउसिंग अफेयर्स रियल एस्टेट पोर्टल 2020
11 Tracking Severe Cyclonic Storm ‘AMPHAN’ (at 2030 Hrs IST)
12 Extension of Lockdown up to May 31, 2020
13 Landfall process has commenced and the forward sector of the wall cloud region is entering into land in West Bengal
14 India’s response to COVID outbreak
15 Lockdown4.0 - States/UTs cannot dilute restrictions imposed in MHA guidelines, can only make them stricter based on local level assessment and Health Ministry Guidelines: MHA
16 6 Cities rated 5 Star, 65 Cities rated 3 Star and 70 Cities rated 1 Star
17 Update at 1730 Hrs IST: Super Cyclonic Storm ‘AMPHAN’ over west-central and adjoining central parts of South Bay of Bengal: Cyclone Warning for West Bengal and north Odisha coasts: Orange Message
18 Position of transactions in Post offices during Covid-19 lockdown
19 Finance Minister announces short term and long-term measures for supporting the poor, including migrants, farmers, tiny businesses and street vendors
20 COVID-19: Relaxation from lockdown in Green zones
21 Effective Implementation of RERA can Restore Trust Between Buyer and Seller: Hardeep S Puri
22 Finance Minister announce measures for relief and credit support related to businesses, especially MSMEs to support Indian Economy’s fight against COVID-19
23 LIST OF 200 (100 PAIRS) MAIL/EXPRESS TRAINS TO BE RUN WEF 01/06/2020
24 Government approves setting up of an Empowered Group of Secretaries (EGoS) and Project Development Cells (PDCs) in Ministries/Departments for attracting investments in India
25 Indian Railways announces timings of Fifteen pair of special trains (thirty trains)
26 CSIR-IIIM & Reliance Industries Limited (RIL) to develop RT-LAMP based test for Coronavirus
27 Ministry of Tourism extends validity period of Approval/Classifications of Hotels & other accommodation units till 30th June 2020
28 Pradhan Mantri Matsya Sampada Yojana (PMMSY) aims to enhance fish production to 220 LMT with an investment of over Rs.20,000 crores in next five years
29 Extension of the last date of Invitation of Nominations for Sardar Patel National Unity Award till 30th June, 2020
30 English rendering of PM’s address in the 12th Episode of ‘Mann Ki Baat 2.0’ on 31.05.2020
31 Dehradun Smart City takes measures including Integrated Command and Control Centre, CCTVs and Lockdown passes to combat COVID-19
32 Food and Immunity: Correlation to combat against COVID-19
33 Cabinet approves adoption of methodology for auction of coal and lignite mines/blocks for sale of coal / lignite on revenue sharing basis and tenure of coking coal linkage
34 Surat Smart City takes key IT initiatives in COVID -19 management and containment
35 Indian Railways restore 03 Special Trains from New Delhi today
36 Second Addendum on Protocol on Inland Water Transit and Trade between India and Bangladesh, 2020
37 Health Secretary interacts with 11 COVID-19 high case load municipal areas
38 IIT Guwahati discovers new ways to prevent memory loss due to Alzheimer
39 Molecular shock absorbers buffer axonal tension of nerve cells
40 Issue of GST late fee for the past period (August 2017 to January 2020) to be discussed in the next GST Council meeting
41 Cabinet approves modifications in the existing Partial Credit Guarantee Scheme (PCGS)
42 Cabinet approves adoption of methodology for auction of coal and lignite mines/blocks for sale of coal / lignite on revenue sharing basis and tenure of coking coal linkage
43 Bollywood and TV actor Sushant Singh Rajput has reportedly committed suicide at his home in Mumbai.
44 Super Cyclonic Storm ‘AMPHAN’ (updated at 2200 Hrs. IST) lay over West Bengal close to Kolkata as a Very Severe Cyclonic Storm: Cyclone warning for West Bengal coast: Red Message
45 Around 42 crore poor people received financial assistance of Rs 53,248 crore under the Pradhan Mantri Garib Kalyan Package
46 Public suggestions invited for amending Motor Vehicle Rules regarding registration of new vehicles, driving licences, and recall of old vehicles
47 Food & PDS Minister says more than 98 LMT food grains lifted through 3530 rail rakes, sufficient 751.69 LMT food grain in stock to meet nation’s food grain requirements during lockdown
48 Efforts to enhance cultivation of Heeng and Saffron
49 Around 76 Online Job Fairs conducted by NCS during lockdown
We would love to hear your thoughts, concerns or problems with anything so we can improve our website educratsweb.com ! visit https://forms.gle/jDz4fFqXuvSfQmUC9 and submit your valuable feedback.
Save this page as PDF | Recommend to your Friends

http://educratsweb(dot)com http://www.educratsweb.com/content.php?id=2387 http://educratsweb.com educratsweb.com educratsweb