Maitreyi Das

just got my summary statement 😭😭

and as I gear up to write a MIRA (re)submission, I'm trying to INTERNALIZE this thread:
more declarative statements, less hedging
more leading w/ conclusions, less leading w/ data
more broad and expansive language, less narrow language

maybe it'll work? 🤷🏽‍♀️

United Methodists lead witness for immigrants | UMNews.org More than 2,000 people of faith marched around the U.S. Capitol to witness to the Christian faith and to let immigrants know that they do not stand alone.

More than 2,000 people gathered on Capitol Hill to worship, sing and march to bring attention to the plight of immigrants in the United States. The event brought together United Methodist bishops, clergy and laity alongside faith leaders from several traditions. www.umnews.org/en/news/unit...

Postdoc job alert in the Crick Institute in London. Are you interested in the actin cytoskeleton? I am looking for a postdoc to examine the cellular, developmental or physiological role of Arp2/3 iso-complex driven actin polymerisation. Multiple aspects available.
crick.ac.uk/WayPostdoc2026

To learn more about this work, please read our preprint. We look forward to your comments and feedback. www.biorxiv.org/content/10.1... 13/end

Our finding indicates that in interphase cells, septins along the cortex prevent Rga4 mobility and localization to the cell ends. When cells enter mitosis, septins are lost from the cell sides, and Rga4 is mobile and does not accumulate to form punctae. 12/

Correspondingly, in its3-1 mutant, we observe enhanced Rga4 punctae. This indicates that the septin cytoskeleton limits Its3-dependent PIP2 levels to promote immobile Rga4 puncta. Increased PIP2 levels as seen in septin mutants promote Rga4 mobility and loss of punctae. 11/

We asked if the presence of septins somehow maintained proper conditions for immobile punctate Rga4 localization. Since Rga4 is membrane bound, we looked at lipid orgnization in septin mutants. we find enhanced PIP2 and its kinase Its3 at the cortex in spn1 mutants, while a decrease in PIP. 10/

Spn3-GFP localized to the mitochondria, and Rga4-mCherry appears diffuse along the cortex.

Next, we asked whether the septin physically interacts with Rga4 to regulate its localization. We do not see any evidence of Septin-Rga4 interaction. However, when we mis-localize septins to the mitochondria with a GBP-Tom20 trap, Rga4 at the cortex is diffuse similar to that in septin mutants. 9/

Montage of time-lapse of Spn3-GFP and Sad1-mCherry expressing cells during mitosis. Red asterisk marks the onset of mitosis. Red boxes highlight decreasing Spn3-GFP filament intensity along the cell side throughout mitosis. Sad1-mCherry labels the spindle pole body and indicates mitosic progression.

When cells enter mitosis, the cortical septin filaments are gradually lost and a medial septin rings appears a the end of anaphase B. 8/

Spn3 and Spn1 colocalize to short filaments along the long axis of interphase cells.

We further investgated Septin organization in interphase cells. We find short septin filaments at the cell cortex along the long axis in interphase. These filaments are lost in dividing cells as the septins organize to form a medial ring. 7/

Cells lacking Spn1 and 4 but not Spn2 and 3 show high septation index, indicating cytokinesis defects. But deletion of each of the 4 septins show high monopolarity index, indicating a polarity defect.

In vegetative fission yeast cells, Spn1 and Spn4 are required for cytokinesis as indicated by high septation index in their mutants. Spn2 and 3 are disposable for cytokinesis, but all 4 septins promote proper polarity. These cells disrupt Cdc42 dynamics and grow from one end and are monopolar. 6/

G. Montage of Rga4-GFP in spn1+ cells during interphase, during mitosis, and in spn1Δ cells during interphase, taken over a 5-minute time-lapse. Red arrowhead marks an Rga4-GFP puncta at the start of the time-lapse. only interphase spn1+ cells show immobile Rga4-GFP puncta along the cell sides. H. Montage of Rga4-GFP recovery after photobleaching during interphase and mitosis in spn1+ and spn1Δ cells taken in 15-second intervals. Red circles indicate the photobleached region of interest (ROI). Red lightning bolt indicates the time point of photobleaching. Rga4-GFP recovers after photo bleaching in spn1Δ regardless of cell cycle phase but not in spn1+ interphase cells. I. FRAP recovery rates of Rga4-GFP signal intensity within the ROI over time in spn1+ and spn1Δ cells during interphase and mitosis. J. T1/2 fluorescence recovery times of listed conditions.

In dividing cells and in cell lacking septin Rga4 along the cortex was mobile as determined by FRAP analysis. 5/

Middle plane images of Rga4-GFP in spn1+ and spn1Δ cells. Red brackets highlight Rga4 distribution along cell sides in interphase cells. Red asterisks highlight dividing cells. Rga4-GFP in interphase cells in spn1Δ appears diffuse and also at teh cell ends.

Years back, we noticed that septin cytoskeleton in interphase decorates the cell sides similar to Rga4. Since septins act as barriers, we investigated their role in Rga4 regulation. We find that in the absence of septins, Rga4 localization in interphase resembles that in dividing cells. 4/

We found that the Cdc42 negative regulator Rga4 that localize to immobile puncta along the cell sides in interphase, appears more diffuse and at the cell ends in dividing cells. We asked what led to this cell-cycle dependent regulation of Rga4 localization. 3/

Cdc42 reactivation at growth sites is regulated by local cell-cycle-dependent loss of its GTPase-activating protein Rga4 in fission yeast Highlighted Article: Resumption of polarized Cdc42 activation at growth sites depends on a cell-cycle cue. This is facilitated by the loss of a Cdc42 GAP, Rga4, from growth sites at the end of cell di...

This story started back in 2021 when we showed that "Cdc42 reactivation at growth sites is regulated by local cell-cycle-dependent loss of its GTPase-activating protein Rga4 in fission yeast " journals.biologists.com/jcs/article/... 2/

I am finally getting around to discussing our preprint "Septins mediate cell-cycle-dependent exclusion of Cdc42 GAP Rga4 from growth sites in fission yeast" by a very talented grad student Justin McDuffie in the Das lab. www.biorxiv.org/content/10.1... 1/

New preprint from us and our friends in the Odorizzi lab at CU-Boulder – we find an apparent role for septin cytoskeletal filaments and vesicle transport from the Golgi to the vacuolar lysosome in budding yeast.

Cdc42 accumulates in aged cells, and reducing its levels extends life span.Two representative WT cells expressing Cdc42-mCherrySW are shown at selected ages and time points (hr: min) from initial loading. White arrowheads indicate cells during or shortly after cytokinesis, when Cdc42 levels are quantified. Black and red arrowheads denote the same cells at other cell cycle stages and cell death, respectively. Scale bar: 3 µm.

Cdc42 is a small GTPase crucial for #CellPolarity, but how does it contribute to #aging when upregulated? This study shows that the ER-anchored chaperone Ydj1 interacts with Cdc42, enhancing its stability & partitioning during asymm #CellDivision & aging in yeast @plosbiology.org 🧪 plos.io/4qz7WaM

The Federal Council is proposing the dissolution of the Swiss Science Council.

Independent fact-based, scientific advice should be available for policy decisions.

Multiple protein structure alignment at scale with FoldMason Protein structure is conserved beyond sequence, making multiple structural alignment (MSTA) essential for analyzing distantly related proteins. Computational prediction methods have vastly extended ou...

FoldMason is out now in @science.org. It generates accurate multiple structure alignments for thousands of protein structures in seconds. Great work by Cameron L. M. Gilchrist and @milot.bsky.social.
📄 www.science.org/doi/10.1126/...
🌐 search.foldseek.com/foldmason
💾 github.com/steineggerla...

PAK-family kinases promote cell fusion irreversibility by preventing cell wall repair https://www.biorxiv.org/content/10.64898/2026.01.27.701985v1

I just woke up from a nap and somehow while I was asleep, everyone on the bus has figured out we are not going to the right place

Work for us Working for us We’re always looking for talented and motivated people to work as part of our close-knit team. Roles range from editorial to production, marketing to event co-ordination, HR to accounts...

Journal of Cell Science @jcellsci.bsky.social is recruiting an enthusiastic and motivated Reviews Editor. An exciting opportunity for a talented scientific editor to make a contribution to an important journal in the field of #cellbiology. Deadline 2 Feb.
More at: www.biologists.com/about-us/wor...

Dinner table with mutton pulao, karahi chicken and raita.

Merry Christmas all. This year we got to celebrate with our family in India. Housefull of kids, nieces and nephews is so much fun. Kept up with tradition and attended midnight service, lots of plum cake and mutton pulao, karahi chicken and raita. The kids loved it.

Hey all, I reached out to the PO of my NIGMS MIRA to ask if the gov't shut down, and rescheduling of study sections, might allow for some accommodation to the standard rule that PIs cannot resubmit a MIRA while their MIRA (or other RPG) is under review (waiting in scores or summary statements) 🧪

I’ll be one of the panelists! I hope to see you there!

@ascbiology.bsky.social 's Women in Cell Biology (WICB) has yet another fantastic event today at 4pm, room 126A. A networking panel on "Thriving in Uncertain Times: Navigating Career and Funding Challenges". #cellbio2025.

If you are at #cellbio2025 you have got to come see "The scripts of Success: Award Winning Scientists Take the Stage with Humor and Honesty" in the CC 108 at 11am today.

The Das lab is well represented at #cellbio2025 in Philly. Come learn more about our research and about the Molecular and Cellular Biology PhD Program at Boston College.

This one is a must see. The title is the talk is "The Importance of Imagination, a Superpower, in Survival, Science, and Our Lives." How cool is that.