Dipa Sashital
@dsashital.bsky.social
Professor of Biochemistry at Iowa State University. Exploring CRISPR biology, mechanisms and structures
Reposted by Dipa Sashital
Ever wondered why some bacteria have multiple CRISPR-Cas systems? Our new study led by Leah Smith shows how type I CRISPR systems can promote the acquisition and retention of new spacers into a co-occuring type III system. www.sciencedirect.com/science/arti...
Type I CRISPR-Cas immunity primes type III spacer acquisition
CRISPR-Cas systems are diverse, with microbes harboring multiple classes and subtypes. Type I DNA-targeting and type III RNA-targeting systems often c…
www.sciencedirect.com
August 18, 2025 at 3:06 PM
Ever wondered why some bacteria have multiple CRISPR-Cas systems? Our new study led by Leah Smith shows how type I CRISPR systems can promote the acquisition and retention of new spacers into a co-occuring type III system. www.sciencedirect.com/science/arti...
Reposted by Dipa Sashital
New preprint: we developed a method that uses phosphoproteome-derived peptide libraries (PhosPropels) for deep specificity profiling of phosphatases and phospholyases www.biorxiv.org/content/10.1...
August 13, 2025 at 5:20 PM
New preprint: we developed a method that uses phosphoproteome-derived peptide libraries (PhosPropels) for deep specificity profiling of phosphatases and phospholyases www.biorxiv.org/content/10.1...
Reposted by Dipa Sashital
First preprint from the Nemudryi Lab! 🍾
In this work, we link antiviral immunity in bacteria and humans by showing that homologs of human Schlafen nucleases protect bacteria from phages.
www.biorxiv.org/content/10.1...
In this work, we link antiviral immunity in bacteria and humans by showing that homologs of human Schlafen nucleases protect bacteria from phages.
www.biorxiv.org/content/10.1...
Bacterial Schlafens mediate anti-phage defense
Human Schlafen proteins restrict viral replication by cleaving tRNA, thereby suppressing protein synthesis. Although the ribonuclease domain of Schlafen proteins is conserved across all domains of lif...
www.biorxiv.org
July 25, 2025 at 2:52 PM
First preprint from the Nemudryi Lab! 🍾
In this work, we link antiviral immunity in bacteria and humans by showing that homologs of human Schlafen nucleases protect bacteria from phages.
www.biorxiv.org/content/10.1...
In this work, we link antiviral immunity in bacteria and humans by showing that homologs of human Schlafen nucleases protect bacteria from phages.
www.biorxiv.org/content/10.1...
Reposted by Dipa Sashital
Was my pleasure to chair the #crispr2025 meeting earlier this year in my hometown in NZ @crisprmeeting.bsky.social
April 11, 2025 at 9:11 PM
Was my pleasure to chair the #crispr2025 meeting earlier this year in my hometown in NZ @crisprmeeting.bsky.social
Reposted by Dipa Sashital
Interested in phage defenses that natively block lytic phage used in therapies?
Or do you want to figure out if a phage has a modified genome?
Meet the END-nucleases, an enzyme family that can broadly restrict phages with many diverse modifications. From talented post-doc Wearn-Xin Yee!
Or do you want to figure out if a phage has a modified genome?
Meet the END-nucleases, an enzyme family that can broadly restrict phages with many diverse modifications. From talented post-doc Wearn-Xin Yee!
April 3, 2025 at 4:15 PM
Interested in phage defenses that natively block lytic phage used in therapies?
Or do you want to figure out if a phage has a modified genome?
Meet the END-nucleases, an enzyme family that can broadly restrict phages with many diverse modifications. From talented post-doc Wearn-Xin Yee!
Or do you want to figure out if a phage has a modified genome?
Meet the END-nucleases, an enzyme family that can broadly restrict phages with many diverse modifications. From talented post-doc Wearn-Xin Yee!
Reposted by Dipa Sashital
I am super excited to share our work uncovering the structure and mechanism of an ATPase-associated reverse transcriptase (RT) involved in prokaryotic antiviral defense, now available as a preprint on bioRxiv!🧬🦠🔬
www.biorxiv.org/content/10.1...
🧵👇
www.biorxiv.org/content/10.1...
🧵👇
Structural basis of antiphage defense by an ATPase-associated reverse transcriptase
Reverse transcriptases (RTs) have well-established roles in the replication and spread of retroviruses and retrotransposons. However, recent evidence suggests that RTs have been conscripted by cells f...
www.biorxiv.org
March 27, 2025 at 1:59 PM
I am super excited to share our work uncovering the structure and mechanism of an ATPase-associated reverse transcriptase (RT) involved in prokaryotic antiviral defense, now available as a preprint on bioRxiv!🧬🦠🔬
www.biorxiv.org/content/10.1...
🧵👇
www.biorxiv.org/content/10.1...
🧵👇
Reposted by Dipa Sashital
Hello BlueSky! Inaugural post here from the Sternberg Lab. We're excited to share our latest work, in which we teamed up with the @WiedenheftLab to study how DRT9 reverse transcriptases provide antiviral immunity. Here’s what we found: www.biorxiv.org/content/10.1...
Protein-primed DNA homopolymer synthesis by an antiviral reverse transcriptase
Bacteria defend themselves from viral predation using diverse immune systems, many of which sense and target foreign DNA for degradation. Defense-associated reverse transcriptase (DRT) systems provide...
www.biorxiv.org
March 26, 2025 at 10:13 PM
Hello BlueSky! Inaugural post here from the Sternberg Lab. We're excited to share our latest work, in which we teamed up with the @WiedenheftLab to study how DRT9 reverse transcriptases provide antiviral immunity. Here’s what we found: www.biorxiv.org/content/10.1...
Reposted by Dipa Sashital
My contribution to the Science Homecoming project--I wrote to The Item in Clinton, MA about the impacts that cuts to science funding will have on our health, our economy, and the opportunities available to young people in Clinton www.clintonitem.com/writes-cuts-...
@sciencehomecoming.bsky.social
@sciencehomecoming.bsky.social
March 14, 2025 at 4:59 PM
My contribution to the Science Homecoming project--I wrote to The Item in Clinton, MA about the impacts that cuts to science funding will have on our health, our economy, and the opportunities available to young people in Clinton www.clintonitem.com/writes-cuts-...
@sciencehomecoming.bsky.social
@sciencehomecoming.bsky.social
Reposted by Dipa Sashital
Finally, in these tough times for science I want to emphasize how this work was supported at every level by NIH: through grants to my lab (DP2); to my students (BTP T32; CBI T32); and from Rohith’s experience as an NIH Postbac in the Tjandra lab. Grateful for the support that made this possible.
March 4, 2025 at 4:28 PM
Finally, in these tough times for science I want to emphasize how this work was supported at every level by NIH: through grants to my lab (DP2); to my students (BTP T32; CBI T32); and from Rohith’s experience as an NIH Postbac in the Tjandra lab. Grateful for the support that made this possible.
Reposted by Dipa Sashital
Excited to share a new preprint! Wireless devices use FM modulation to transmit multiplexed noise-resistant data. Led by @born2raisecell.bsky.social, we create a biochemical analogue of this paradigm using genetically encoded oscillators (GEOs) for single-cell FM streaming tinyurl.com/nbs8rw42 🧵
March 4, 2025 at 4:28 PM
Excited to share a new preprint! Wireless devices use FM modulation to transmit multiplexed noise-resistant data. Led by @born2raisecell.bsky.social, we create a biochemical analogue of this paradigm using genetically encoded oscillators (GEOs) for single-cell FM streaming tinyurl.com/nbs8rw42 🧵
Reposted by Dipa Sashital
CRISPR-Cas supervises diverse anti-phage defense systems https://www.biorxiv.org/content/10.1101/2024.12.27.630466v1
December 27, 2024 at 4:17 PM
CRISPR-Cas supervises diverse anti-phage defense systems https://www.biorxiv.org/content/10.1101/2024.12.27.630466v1
Reposted by Dipa Sashital
Finishing the year with a paper submission always feels good! 🛡 🦠 (1/5)
www.biorxiv.org/content/10.1...
Happy holidays everyone! ⭐️🎄
www.biorxiv.org/content/10.1...
Happy holidays everyone! ⭐️🎄
Systematic functional assessment of antiphage systems in their native host
Bacterial resistance to bacteriophages (phages) relies on two primary strategies: preventing phage attachment and blocking post-attachment steps. These latter mechanisms are mediated by defence system...
www.biorxiv.org
December 22, 2024 at 8:42 PM
Finishing the year with a paper submission always feels good! 🛡 🦠 (1/5)
www.biorxiv.org/content/10.1...
Happy holidays everyone! ⭐️🎄
www.biorxiv.org/content/10.1...
Happy holidays everyone! ⭐️🎄
Reposted by Dipa Sashital
Is it “winner-takes all” when the simplest living things compete? Check out my fresh publication on phage coexistence in Science and a thread below🧵 www.science.org/doi/10.1126/...
Diverse phage communities are maintained stably on a clonal bacterial host
Bacteriophages are the most abundant and phylogenetically diverse biological entities on Earth, yet the ecological mechanisms that sustain this extraordinary diversity remain unclear. In this study, w...
www.science.org
December 12, 2024 at 7:22 PM
Is it “winner-takes all” when the simplest living things compete? Check out my fresh publication on phage coexistence in Science and a thread below🧵 www.science.org/doi/10.1126/...
Reposted by Dipa Sashital
If you were on the fence about coming to CRISPR 2025 let us add that Christchurch airport is well connected internationally and from there you can explore many grand sights in the South Island, NZ. Register now and book a conference trip to NZ hashtag#CRISPR2025 lnkd.in/gaSkt-Ng
December 9, 2024 at 11:13 PM
If you were on the fence about coming to CRISPR 2025 let us add that Christchurch airport is well connected internationally and from there you can explore many grand sights in the South Island, NZ. Register now and book a conference trip to NZ hashtag#CRISPR2025 lnkd.in/gaSkt-Ng
Reposted by Dipa Sashital
Happy Holidays from the Weeks lab! This year's ornament is a working ferris wheel 🎡☃️
December 11, 2024 at 4:08 PM
Happy Holidays from the Weeks lab! This year's ornament is a working ferris wheel 🎡☃️
Reposted by Dipa Sashital
Meet one of our speakers: Elizabeth Kellogg is an assistant professor in the department of Molecular Biology and Genetics at Cornell. There's still time to register and get to hear Elizabeth speak at CRISPR 2025 in Ōtautahi, Christchurch, NZ. lnkd.in/gds9sURN
December 9, 2024 at 11:11 PM
Meet one of our speakers: Elizabeth Kellogg is an assistant professor in the department of Molecular Biology and Genetics at Cornell. There's still time to register and get to hear Elizabeth speak at CRISPR 2025 in Ōtautahi, Christchurch, NZ. lnkd.in/gds9sURN
Reposted by Dipa Sashital
First paper of our lab today @natureportfolio.bsky.social by Nussi!
We provide a real-time movie on how #transcription and #translation cooperate using #single-molecule FM: we find long-range #ribosome/ RNAP communication mediated by #RNA looping!
@embl.org #RNAbiology #RNASky
t.co/a24Xxcxdo0
We provide a real-time movie on how #transcription and #translation cooperate using #single-molecule FM: we find long-range #ribosome/ RNAP communication mediated by #RNA looping!
@embl.org #RNAbiology #RNASky
t.co/a24Xxcxdo0
December 4, 2024 at 8:53 PM
First paper of our lab today @natureportfolio.bsky.social by Nussi!
We provide a real-time movie on how #transcription and #translation cooperate using #single-molecule FM: we find long-range #ribosome/ RNAP communication mediated by #RNA looping!
@embl.org #RNAbiology #RNASky
t.co/a24Xxcxdo0
We provide a real-time movie on how #transcription and #translation cooperate using #single-molecule FM: we find long-range #ribosome/ RNAP communication mediated by #RNA looping!
@embl.org #RNAbiology #RNASky
t.co/a24Xxcxdo0
Reposted by Dipa Sashital
It’s a wrap! The final version of our paper is out 🎉 where we characterize the multifaceted response of the transcript-activated type III CRISPR-Cas immunity. Here’s a skytorial (bluetorial?) by my awesome co-lead @akshilton.bsky.social
#RNA #RNAsky #WomenInSTEM
#RNA #RNAsky #WomenInSTEM
Incredibly proud to share my thesis work, co-led by @naamaaviram.bsky.social available now at Cell Host Microbe! Cells use growth arrest as a defense against stress and viruses. Here we thoroughly characterize the arrest associated with CRISPR Type III immunity. www.cell.com/cell-host-mi...
DEFINE_ME
www.cell.com
December 4, 2024 at 3:12 PM
It’s a wrap! The final version of our paper is out 🎉 where we characterize the multifaceted response of the transcript-activated type III CRISPR-Cas immunity. Here’s a skytorial (bluetorial?) by my awesome co-lead @akshilton.bsky.social
#RNA #RNAsky #WomenInSTEM
#RNA #RNAsky #WomenInSTEM
Reposted by Dipa Sashital
Rumour is there are cheaps flights from North America to NZ at the moment 👀✈️- get in quick and book your flights now for CRISPR 2025. Registrations are still open and we would love to see you. The airport is just a short trip to the city! crispr2025.org/registration
December 3, 2024 at 10:44 PM
Rumour is there are cheaps flights from North America to NZ at the moment 👀✈️- get in quick and book your flights now for CRISPR 2025. Registrations are still open and we would love to see you. The airport is just a short trip to the city! crispr2025.org/registration
Reposted by Dipa Sashital
This week in @science.org Molecular basis of #mRNA delivery to the bacterial #ribosome www.science.org/doi/10.1126/...
Molecular basis of mRNA delivery to the bacterial ribosome
Protein synthesis begins with the formation of a ribosome-messenger RNA (mRNA) complex. In bacteria, the small ribosomal subunit (30S) is recruited to many mRNAs through base pairing with the Shine-Da...
www.science.org
November 29, 2024 at 12:37 PM
This week in @science.org Molecular basis of #mRNA delivery to the bacterial #ribosome www.science.org/doi/10.1126/...
Reposted by Dipa Sashital
I have registered to attend #CRISPR 2025. If you are going, I look forward to meeting there www.crispr2025.org
CRISPR 2025 Conference, , Christchurch New Zealand
We are excited to welcome you to Ōtautahi Christchurch, New Zealand for the CRISPR 2025 Conference. For the very first time, the annual CRISPR meeting is venturing into the Southern Hemisphere, making...
www.crispr2025.org
November 29, 2024 at 2:21 PM
I have registered to attend #CRISPR 2025. If you are going, I look forward to meeting there www.crispr2025.org
Reposted by Dipa Sashital
Very excited to share the first story from my postdoc where we uncover the structural basis for slow Cas9 turnover!
We use kinetics-guided cryo-EM to capture 25 conformational states of SpCas9 from a single dataset - including the first look at Cas9 releasing product.
biorxiv.org/content/10.1...
We use kinetics-guided cryo-EM to capture 25 conformational states of SpCas9 from a single dataset - including the first look at Cas9 releasing product.
biorxiv.org/content/10.1...
November 28, 2024 at 12:32 PM
Very excited to share the first story from my postdoc where we uncover the structural basis for slow Cas9 turnover!
We use kinetics-guided cryo-EM to capture 25 conformational states of SpCas9 from a single dataset - including the first look at Cas9 releasing product.
biorxiv.org/content/10.1...
We use kinetics-guided cryo-EM to capture 25 conformational states of SpCas9 from a single dataset - including the first look at Cas9 releasing product.
biorxiv.org/content/10.1...
Reposted by Dipa Sashital
Awesome new work from Sam Butcher's lab--including a 1 angstrom structure of a new pUG RNA!
Self-assembly and condensation of intermolecular poly(UG) RNA quadruplexes academic.oup.com/nar/article/...
Self-assembly and condensation of intermolecular poly(UG) RNA quadruplexes academic.oup.com/nar/article/...
Self-assembly and condensation of intermolecular poly(UG) RNA quadruplexes
Abstract. Poly(UG) or ‘pUG’ dinucleotide repeats are highly abundant sequences in eukaryotic RNAs. In Caenorhabditis elegans, pUGs are added to RNA 3′ ends
academic.oup.com
November 25, 2024 at 5:41 PM
Awesome new work from Sam Butcher's lab--including a 1 angstrom structure of a new pUG RNA!
Self-assembly and condensation of intermolecular poly(UG) RNA quadruplexes academic.oup.com/nar/article/...
Self-assembly and condensation of intermolecular poly(UG) RNA quadruplexes academic.oup.com/nar/article/...