#cell and molecular biology

[reasonsforhope]

"A team at Northwestern University has come up with the term “dancing molecules” to describe an invention of synthetic nanofibers which they say have the potential to quicken the regeneration of cartilage damage beyond what our body is capable of.

The moniker was coined back in November 2021, when the same team introduced an injection of these molecules to repair tissues and reverse paralysis after severe spinal cord injuries in mice.

Now they’ve applied the same therapeutic strategy to damaged human cartilage cells. In a new study, published in the Journal of the American Chemical Society, the treatment activated the gene expression necessary to regenerate cartilage within just four hours.

And, after only three days, the human cells produced protein components needed for cartilage regeneration, something humans can’t do in adulthood.

The conceptual mechanisms of the dancing molecules work through cellular receptors located on the exterior of the cell membrane. These receptors are the gateways for thousands of compounds that run a myriad of processes in biology, but they exist in dense crowds constantly moving about on the cell membrane.

The dancing molecules quickly form synthetic nanofibers that move according to their chemical structure. They mimic the extracellular matrix of the surrounding tissue, and by ‘dancing’ these fibers can keep up with the movement of the cell receptors. By adding biological signaling receptors, the whole assemblage can functionally move and communicate with cells like natural biology.

“Cellular receptors constantly move around,” said Northwestern Professor of Materials Sciences Samuel Stupp, who led the study. “By making our molecules move, ‘dance’ or even leap temporarily out of these structures, known as supramolecular polymers, they are able to connect more effectively with receptors.”

The target of their work is the nearly 530 million people around the globe living with osteoarthritis, a degenerative disease in which tissues in joints break down over time, resulting in one of the most common forms of morbidity and disability.

“Current treatments aim to slow disease progression or postpone inevitable joint replacement,” Stupp said. “There are no regenerative options because humans do not have an inherent capacity to regenerate cartilage in adulthood.”

In the new study, Stupp and his team looked to the receptors for a specific protein critical for cartilage formation and maintenance. To target this receptor, the team developed a new circular peptide that mimics the bioactive signal of the protein, which is called transforming growth factor beta-1 (TGFb-1).

Northwestern U. Press then reported that the researchers incorporated this peptide into two different molecules that interact to form supramolecular polymers in water, each with the same ability to mimic TGFb-1...

“With the success of the study in human cartilage cells, we predict that cartilage regeneration will be greatly enhanced when used in highly translational pre-clinical models,” Stupp said. “It should develop into a novel bioactive material for regeneration of cartilage tissue in joints.”

“We are beginning to see the tremendous breadth of conditions that this fundamental discovery on ‘dancing molecules’ could apply to,” Stupp said. “Controlling supramolecular motion through chemical design appears to be a powerful tool to increase efficacy for a range of regenerative therapies.”"

-via Good News Network, August 5, 2024

[mindblowingscience]

At some early point in Earth's history, a collection of increasingly complex chemicals performed a new trick. They somehow transformed themselves, with help from a jolt of energy, into an energy-producing and self-replicating cell. The timing of this critical moment in Earth's history is hidden behind the passing of billions of years.

Continue Reading.

[computers-best-friend]

I was in bio the other week and thinking about mitochondria (as you do) and I kept thinking about a heavy metal poster that was mitochondria and like

I did it lol

[wikipediapictures]

MTT assay

“A 96-well microtiter plate used in an MTT assay. Each column was incubated with different amounts of culture cells, increasing from 500 cells in column 2 (left) to 100.000 cells in column 11 (right), for 72 hours. After a short incubation with MTT, the purple formazan product was extracted using Dimethyl sulfoxide. As can be seen, higher amounts of cells result in higher formazan production and thus a stronger purple colour.” - via Wikimedia Commons

[theerlenmeyerflask]

I am still stuck on the same data analysis (but finally towards the end !). To avoid posting the same desk pic for days in a row, I'll have you meet my lil study buddy 🥰

[annabethy]

What do u mean I graduate in a month

[er-cryptid]

S. moniliformis

Patreon

[katiajewelbox]

Plant Immune System Part 3

The plant immune system is the topic of my PhD thesis, which I'm currently writing following several years of lab-based research as a PhD student at Imperial College London under the supervision of Professor Colin Turnbull.

Here's an introduction to my research, which focused on how certain plants defend themselves against aphids.

Aphids are an important insect pest that threaten agriculture worldwide. As we learned in the previous post, plant resistance (R) genes control resistance to specific pests and pathogens through interaction with effectors from the invaders. Since examples of R gene-dependent aphid resistance have been documented in different plant species, aphid-specific R genes may enable the development of resistant crops.

In the model plant Medicago truncatula, there are some varieties that are resistant to aphids and other varieties that are susceptible to Pea Aphids (Acyrthosiphon pisum). Whether the plant is resistant also depends on the variety of aphid. In my project, the A17 plant is resistant to PS01 aphids but not to N116 aphids, while the DZA plant is susceptible to both aphid varieties.

What is the key difference in the resistant versus susceptible plants? Resistant A17 plants have a portion of their genome “Resistance to Acyrthosiphon pisum 1” (RAP1) which determines resistance to PS01 aphids, but the genes controlling the defence response and physiological defence mechanisms remain unknown. Two candidate R genes located in RAP1, designated “RAP1A” and “RAP1B”, may control resistance.

My main objective in my PhD project has been to determine whether RAP1A and RAP1B control aphid resistance, and to investigate the RAP1-mediated defence response. I look forward to sharing the findings in publications and in talks next year!

Image credit: Original diagram by Katia Hougaard with images from the Turnbull Lab.

#katia_plantscientist#science#biology#research#plants#botany#plantbiology#phdproject#plantbiology#plantscience#sciencecommunication#diagrams#phd#imperialcollegelondon#phdthesis#medicago#aphid#plantimmunesystem#pestsandpathogens#plantpathology#womeninscience#plantbiologist

[wackyweirdwriter]

Finals Week is here, and ya know what that means? Ikemen Vampire has found its way into my studying once again.

This really does help me remember stuff better. Highly recommend it if you find it works for you. It also just makes studying more fun.

[thegenecatist]

Cat Color Basics: Eumelanin and Phaeomelanin

In mammals, there are a type of cells located in the skin called melanocytes. These cells produce a pigment called melanin which is responsible for the color of their skin and fur. There are two types of melanin; eumelanin and phaeomelanin. Eumelanin is black and brown pigment, while phaeomelenin is red pigment. The wide variety in the color of cats that we see are an outcome from mutations in the genes that result in modifications of pigment production, granule placement, and more.

Eumelanin-based colors

Phaeomelanin-based colors

Note: Breeders may call these colors by other names, such as black being labeled ebony

[gaymarisa]

i love lecture recordings, i genuinely love listening to these like podcasts. this is entertainment to me, fun, learning in a way that does not bore me!

the moment they give me a single 10 page article though it takes me 5 business weeks to read it

[mindblowingscience]

Fifty years since its discovery, scientists have finally worked out how a molecular machine found in mitochondria allows us to make the fuel we need from sugars, a process vital to all life on Earth. Scientists at the Medical Research Council (MRC) Mitochondrial Biology Unit, University of Cambridge, have worked out the structure of this machine and shown how it operates like the lock on a canal to transport pyruvate—a molecule generated in the body from the breakdown of sugars—into our mitochondria.

Continue Reading.

[startfirstbd]

Limitations of cell theory:

The cell theory has several limitations, such as-

◾Viruses, virions and prions - have no cellular structure.

◾ Connective tissue contains a lot of extracellular VO material or matrix.

◾Bacteria and archaebacteria do not have a well-structured nucleus. 

◾Consequently cytoplasm and red blood cells have no nucleus.

◾The protoplasm of animal skin and plant bark cells is replaced by dead matter.

◾ Some algae (Vaucheria), six (Rhizopus, Mucor) and ciliates have synocytic (Coenocytic) structure, that is, they have a large number of free nuclei in their cytoplasm.

[somnanana]

When I found out about Flippase and Floppase in Intro to Cell and Molecular Biology (iirc), thats when I knew that microbiologists were just screwing around.

Then I found out about piRNA, which binds and interacts with PIWI (P-element Induced Wimpy Testis in Drosophilia) proteins…

And later on about the sex-determining gene in the Y chromosome being called the SRY (read: sorry) gene…

Keep on keeping on, cell biologists/geneticists!