Welcome to the eight issue of the MolBio Carnival! Some great blog posts on molecular and cellular biology have been submitted to this edition. So let’s not waste any time and get this carnival started, because there’s much to read and learn.
Molecular biologists study life at its tiniest scale. Their world is both fascinating and mysterious, but I never regarded it as beautiful. Beauty is the domain of those fields of biology that study exotic creatures and ancient fossils, and not that of those who study nature with a microscope and a pipette. Or so I thought. My view changed when, at the end of my second year in college, one of my teachers showed the following video to our class:
Suddenly, the cell came to life. It became a bustling city where proteins and molecules were doing their jobs, and through their collective actions sustain a complex, living machine. Thanks to the great writers that contributed blog posts for this edition, I can present you a taste of all the wonderful things that happen within our cells.
Imagine a cell. Today, an animal cell will do. Our imagined cell is not floating in empty space. It is embedded into a matrix of proteins and sugars. This matrix provides support, but is also flexible enough to bend and stretch when needed. Michael Scott Long from phased writes how deforming this elastic matrix can make it easier for cancer cells to grow deeper into tissues.
Between the tangled proteins of the extracellular matrix, we find our cell. The lipids of its cellular membrane are bobbing up and down. Before we enter our cell, we’d better ring the bell. Not only would it be impolite to barge in – it would also be nigh impossible. The lipid membrane is a formidable barrier to all kinds of ions, proteins and other molecules. The cell’s doorbells are its signalling receptors that raft on the lipid sea. When a molecule binds this receptor, the word of its arrival gets spread on the other side of the membrane via signal molecules that are released. Lab Rat wrote a post on these signal molecules, which appear to be more complex and versatile than was previously known.
Some molecules, such as the hormones estradiol and testosterone, have no need for doorbells: they can pass the membrane on their own. Once they are in the cell, a protein ferry picks them up and brings them straight to the cell’s core, where all the DNA is located. Once it is there, the molecule switches on certain genes and turns off others. But why use the ferry boat at all? Why don’t the molecules bind the DNA themselves? Over at the It Takes 30 blog, Becky Ward gives the answer in a blog post on the signalling networks. There you will also read that the entire mechanism is way more complex than I just summarized (over 100 molecules are involved in the entire process!).
While we’re in the cell’s nucleus, we might as well look around us and see what’s going on here. Katie Pratt explains: the information that lies in the DNA is read and converted into RNA. These RNA molecules contain the instructions for making functional proteins. But some RNAs lack these instructions. Their sole purpose is to regulate the activity of other genes. Scientists use these RNAs to silence the genes they want to study. They even think about using them to repress the genes of virusses such as HIV, as a potential therapy. Head over to Katie’s blog to find out more.
Our imagined cell is not infected by HIV, luckily. We can safely follow a messenger RNA molecule as it squeezes through the nuclear pore on its way to the ribosome. There, its encoded message is translated into an enzyme. Enzymes are pipelines of our cell. By catalyzing chemical reactions, they can direct the flow of small molecules within the cell. Christopher Dieni on Bitesizebio tells you everything you want to know about enzymes. Seriously, it’s a great overview of all the things that enzymes do and don’t do, so go check it out!
That’s it for this month’s edition of The MolBio Carnival. I hope you enjoyed the journey. You can check future hosts and past editions on the Carnival’s home page. Be sure to subscribe to the RSS feed to receive notifications and summaries when new editions of the Carnival are posted. Also, you are welcomed to submit your best molbio blog articles to the next edition of The MolBio Carnival, which will be hosted by Alex from Alles was lebt.
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Lucas, you have an incredible talent for weaving all of your featured posts together into a single cohesive, elegant, and compelling story. Thanks for doing this, and also for featuring my post alongside all these other inspiring posts.
Thanks Christopher, that’s really nice to hear! It’s been a pleasure once again. I really enjoyed your post, I wish my younger self could’ve read it when he was still following biochemistry classes!
hi,
I loved this concept of Mol Bio Carnival!..
I am a Master’s student doing MSc by research in Biology @ Tata Institute of Fundamental Research, Mumbai, India. I work in the field of cell biology and dev. biology.
I appreciate the efforts of all of you to explain the biological phenomena or concepts to common people. I would definitely like to do something like this in future!!
Jaydeep.
Hi Jaydeep! I’m glad you enjoyed the carnival. If you ever decide to write a blog post about molecular or cellular biology, be sure to submit it to the carnival, and you’ll be featured as well :).
Hey Lucas, you’re such a great story teller! :D