Mastodawn

Yet another wrinkle on the Central Dogma of Molecular Biology: protein-templated DNA synthesis!

ABSTRACT
Defense-associated reverse transcriptases (DRTs) are widespread bacterial anti-phage systems that use unconventional mechanisms of polynucleotide synthesis. We show that DRT3, which comprises two distinct RTs (Drt3a and Drt3b) and a noncoding RNA (ncRNA), synthesizes alternating poly(GT/AC) double-stranded DNA. Cryo–electron microscopy structures at 2.6 Å resolution reveal a D3-symmetric 6:6:6 complex of Drt3a, Drt3b, and ncRNA. Drt3a produces the poly(GT) strand using a conserved ACACAC template within the ncRNA. Notably, Drt3b synthesizes a complementary, protein-primed poly(AC) strand in the complete absence of a nucleic acid template, using conserved active site residues specific to Drt3b to enforce precise base alternation. These findings expand the functional landscape of nucleic acid polymerases, revealing a protein-templated mechanism for sequence-specific DNA synthesis.

https://www.science.org/doi/10.1126/science.aed1656

#centraldogma #molecularbiology #Drt3

Scientific Frontline 17h ago

Dicitriosides are newly identified triterpenoid compounds discovered in a plant extract that demonstrate potent, broad-spectrum antiviral activity against the #Ebola virus and #SARS-CoV-2. These rare natural molecules offer significant therapeutic potential at pharmacologically achievable concentrations.
#Virology #Pharmacognosy #MolecularBiology #Pharmacology #sflorg
https://www.sflorg.com/2026/04/vi04302601.html

Using plants to fight Ebola and COVID-19

Scientists have discovered dicitriosides, rare plant compounds with potent antiviral activity against Ebola and COVID-19, offering new pandemic hope.

海草 1d ago

There’s a motor on this thing’s tail. 🦠⚙️
Scientists studied it for 50 years. Last month? They finally figured out how it spins.
The bacterial flagellar motor. 45 nanometers wide. 30 proteins, self-assembled. Runs on protons, not batteries. Reverses direction instantly.
After 50 years of work, one researcher said: "My lifelong pursuit is now realized."
Nature’s nano-engineering. Absolute perfection.

#BacterialMotor #MolecularBiology #CryoEM #NatureEngineering #ScienceBreakthrough #FlagellarMotor

Scientific Frontline 1d ago

A novel gene-editing technology that enables the efficient insertion of extremely large segments of DNA into a genome, shifting the potential of gene therapy from merely correcting small mutations to replacing entire genes.
#Genetics #MolecularBiology #Biochemistry #sflorg
https://www.sflorg.com/2026/04/gen04292601.html

New technology enables ‘rewriting a chapter’ of the genome

Study shows efficient insertion of large DNA segment in place of gene

Scientific Frontline 2d ago

The p53 protein, widely known as the "guardian of the genome," is a crucial tumor suppressor that is mutated in approximately half of all cancer cases; researchers have engineered miniature antibodies called DARPins to stabilize these mutated proteins and restore their protective function.
#Oncology #MolecularBiology #BiophysicalChemistry #Pharmaceutical #sflorg
https://www.sflorg.com/2026/04/ongy04292601.html

Mini-Antibodies Reactivate the Guardian of the Genome

With more than 2,000 distinct p53 mutations identified across different cancers, developing customized treatments for each variant is highly impractic

Scientific Frontline 2d ago

Researchers at the University of Queensland have discovered that the disruption of a specific cellular protein, known as PRICKLE1, directly impairs the formation of the neural tube during embryonic development. This disruption prevents the upper and lower sections of the spinal cord from fusing correctly, resulting in junctional neural tube defects.
#Embryology #DevelopmentalBiology #Teratology #MolecularBiology #sflorg
https://www.sflorg.com/2026/04/bio04292601.html

Quail embryos + a prickly protein = major discovery in birth defects

Researchers observed in real time how disruption from a cell protein during neural tube formation causes birth defects like spina bifida.

Scientific Frontline 2d ago

SMART (Single-Molecule Assay on Ribonucleic acid by Translated product) is an advanced in vitro selection platform designed to accelerate directed enzyme evolution. It significantly reduces the time and cost required to identify superior enzyme variants by tracking them at the single-molecule level.
#SyntheticBiology #MolecularBiology #Biochemistry #Biotechnology #sflorg
https://www.sflorg.com/2026/04/sybi04282601.html

Scientists pave the way for fast, cost-effective custom enzyme development

Enzymes are proteins that catalyze chemical reactions in living organisms

Scientific Frontline 3d ago

Exosomes containing signaling molecules derived from wild Scandinavian flatworms can significantly accelerate tissue repair and wound healing in human skin models.
#ChemicalBiology #RegenerativeMedicine #MolecularBiology #Therapeutics #sflorg
https://www.sflorg.com/2026/04/bio04282601.html

Wild flatworms heal wounds

The study suggests that signaling molecules from flatworms can accelerate the human body’s own healing processes

mymedschool 3d ago

Molecular mechanism of cancer metastasis and invasion USMLE
#USMLEStep1 #MedEd #Pathology #Oncology #Metastasis #CancerBiology #Microbiology #Step1Prep #HighYield #MedSchool #InfectiousDisease #MolecularBiology #FutureDoctor #StudyGram #MedTwitter #Anki #BoardExams #MedicalStudent #FirstAid #Medical

https://mymedschool.org/portfolio/u01-17-065-tissue-invasion-metastasis/?utm_source=mastodon&utm_medium=jetpack_social

U01.17.065 Cancer Pathogenesis: The Metastatic Cascade and Tissue Invasion

Master the steps of tissue invasion and metastasis (U01.17.065) for USMLE Step 1. Learn the molecular mechanisms of E-cadherin loss, basement membrane degradation, and the seed-and-soil hypothesis. High-yield guide on mymedschool.org.

mymedschool.org

mymedschool 3d ago

How cancer cells achieve replicative immortality telomerase USMLE

#USMLEStep1 #MedEd #Pathology #CancerBiology #Oncology #Telomerase #MolecularBiology #Step1Prep #HighYield #MedSchool #Genetics #CellBiology #FutureDoctor #StudyGram #MedTwitter #Anki #BoardExams #MedicalStudent #FirstAid #MedicalSch

https://mymedschool.org/portfolio/u01-17-064-replicative-potential-of-cancer-cells/?utm_source=mastodon&utm_medium=jetpack_social

U01.17.064 Replicative Potential of Cancer Cells: Telomerase and Immortality

Master the hallmarks of cancer (U01.17.064) for USMLE Step 1. Learn how cancer cells achieve replicative immortality through telomerase activation and the evasion of senescence. High-yield guide on mymedschool.org.

mymedschool.org