Tag Archives: Science

Congratulations to Yansong Miao on his new paper!

Yansong Miao‘s new paper is out now at The Proceedings of the National Academy of Sciences.  Congratulations to Yansong on his great work!  The abstract is below.  The PDF can be downloaded from PNAS here.

Cell-cycle regulation of formin-mediated actin cable assembly. Miao Y, Wong CC, Mennella V, Michelot A, Agard DA, Holt LJ, Yates JR 3rd, Drubin DG. Proc Natl Acad Sci U S A. 2013 Nov 19;110(47):E4446-E4455. Epub 2013 Oct 16.  PMID: 24133141

Abstract

Assembly of appropriately oriented actin cables nucleated by formin proteins is necessary for many biological processes in diverse eukaryotes. However, compared with knowledge of how nucleation of dendritic actin filament arrays by the actin-related protein-2/3 complex is regulated, the in vivo regulatory mechanisms for actin cable formation are less clear. To gain insights into mechanisms for regulating actin cable assembly, we reconstituted the assembly process in vitro by introducing microspheres functionalized with the C terminus of the budding yeast formin Bni1 into extracts prepared from yeast cells at different cell-cycle stages. EM studies showed that unbranched actin filament bundles were reconstituted successfully in the yeast extracts. Only extracts enriched in the mitotic cyclin Clb2 were competent for actin cable assembly, and cyclin-dependent kinase 1 activity was indispensible. Cyclin-dependent kinase 1 activity also was found to regulate cable assembly in vivo. Here we present evidence that formin cell-cycle regulation is conserved in vertebrates. The use of the cable-reconstitution system to test roles for the key actin-binding proteins tropomyosin, capping protein, and cofilin provided important insights into assembly regulation. Furthermore, using mass spectrometry, we identified components of the actin cables formed in yeast extracts, providing the basis for comprehensive understanding of cable assembly and regulation.

Miao 2013 PNAS Figure 2

Average intensity projections along the z-axis of WT cells stained with Alexa-568 phalloidin to label actin filaments and expressing GFP-Tub1 as a cell-cycle stage indicator, obtained using 3D SIM microscopy.

Journal Club on Monday, August 6

For Journal Club on August 6, Eric Lewellyn presented the following paper:

Actin filament severing by cofilin dismantles actin patches and produces mother filaments for new patches. Chen Q, Pollard TD. Curr Biol. 2013 Jul 8;23(13):1154-62. PMID: 23727096.

Chen & Pollard Curr Biol 2013

“Sever, diffuse and trigger” model for actin filament turnover in actin patches. The 7 steps (numbers next to the arrows) are (1) clathrin coated pits bind adaptor proteins End4p and Pan1p, (2) short, diffusing actin filaments bind to End4p and Pan1p associated with coated pits, and (3) Arp2/3 complex interacts with these mother filaments and nucleation promoting factors to (4) initiate branching nucleation of actin filaments that promote elongation of the endocytic tubule. (5) After abscission of the vesicle, (6) cofilin severs actin filaments to generate a pool of short, diffusing actin filaments, some of which return to the cycle at step 2.

Journal Club on Monday, July 22

For Journal Club on July 22, Connie Peng presented the following paper:

Mps1 and Ipl1/Aurora B act sequentially to correctly orient chromosomes on the meiotic spindle of budding yeast. Meyer RE, Kim S, Obeso D, Straight PD, Winey M, Dawson DS. Science. 2013 Mar 1;339(6123):1071-4. PMID: 23371552

Meyer Science 2013

Meyer Science 2013

 

Microtubules and Mitosis Journal Club on Thursday, May 23

For Microtubules and Mitosis Journal Club on April 25, members of the Drubin/Barnes Lab, Eva Nogales Lab, and Ahmet Yildiz Lab discussed the following paper, selected by Anthony Cormier:

Tension sensing by Aurora B kinase is independent of survivin-based centromere localization. Campbell CS, Desai A. Nature. 2013 May 2;497(7447):118-21. PMID: 23604256.

Campbell Nature 2013

Model for mechanism of chromosome biorientation.

Microtubules and Mitosis Journal Club on Thursday, April 25

For our new Microtubules and Mitosis Journal Club on April 25, members of the Drubin/Barnes Lab, Eva Nogales Lab, and Ahmet Yildiz Lab discussed the following paper, selected by Nate Krefman:

Estimating the microtubule GTP cap size in vivo. Seetapun D, Castle BT, McIntyre AJ, Tran PT, Odde DJ. Curr Biol. 2012 Sep 25;22(18):1681-7. PMID: 22902755

Example EB1 comet from an EB1-EGFP LLCPK1 cell and the corresponding fluorescence intensity (FI) linescan, blue line.

Journal Club on Thursday, April 18

For our Journal Club on April 18, Akemi Kunibe presented the following paper:

Endoplasmic reticulum-associated mitochondria-cortex tether functions in the distribution and inheritance of mitochondria. Lackner LL, Ping H, Graef M, Murley A, Nunnari J.  Proc Natl Acad Sci U S A. 2013 Feb 5;110(6):E458-67. PMID: 23341591.

The ER is a component of the Num1 mitochondria–cell cortex tether.

Journal Club on Monday, March 17

For our Journal Club on March 17, Rebecca Lu will present the following paper:

Robust polarity establishment occurs via an endocytosis-based cortical corralling mechanism. Jose M, Tollis S, Nair D, Sibarita JB, McCusker D. J Cell Biol. 2013 Feb 18;200(4):407-18. PMID: 23401000

Schematics illustrating the mathematical model. Shown are the Cdc42 autoamplification module (A), the complete endocytosis module (B), the exocytosis module (C), and a legend for graphics (D).

37 Degrees perform “I Want to Graduate” live at MCB Follies!

Synthetic boy band 37 Degrees made a surprise live performance at MCB Follies this year.  Before a screaming hoard of desperate graduate students, 37 Degrees performed their new single “I Want to Graduate.”  You may recognize the song as a parody of the Backstreet Boys single “I Want it That Way.”

You may also recognize one of the members of 37 Degrees as Nate Krefman, a graduate student in the Drubin/Barnes Lab!  The other participants in this transient complex are fellow MCB graduate students Phil Cleves and Andrew Glazer from Craig Miller’s Lab (also from “I’m Bringin’ Stickleback”), Alec Sexton from Cathy Collins’ Lab (also from “Grad School Pressure”), and Brock Roberts from Henk Roelink’s Lab (also from “Vol II: How to Do a DNA Mini-Prep (Molecular and Cell Biology Training Video Series”).

37 DEGREES is Nate Krefman, Phil Cleves, Andrew Glazer, Alec Sexton, & Brock Roberts

CONCEPT: Meru S.
LYRICS: Meru S. & Nate Krefman
PRE-RECORDED VOCALS: Nate Krefman
LIVE VOCALS: 37 Degrees
CAMERA: David McCleary
SLIDESHOW & VIDEO EDITING: Nate Krefman

________________________________________________

LYRICS:

Nate:
It is my fire —
my one desire.
Believe when I say:
I want to graduate.

Phil:
But we are two worlds apart,
Just years from the start.
It’s your fate:
You’ll never graduate.

All:
Tell me when…
I’m begging my committee.
Tell me when…
Be in grad school till I’m fifty.
Tell me when…
You never wanna hear me say:
I want to graduate

Andrew:
It will be so wrong,
If this just goes on.
Please don’t come too late.
Cuz I want to graduate.

All:
Tell me when…
All my friends are wearing Polo.
Tell me when…
But I’m still dressing like a hobo.
Tell me when…
You never wanna hear me say:
I want to graduate.

Phil:
Now I can see that you wanna depart —
But not if it’s up to me. Yeah.
No matter your progress,
I want you to know,
There’s no way you’ll ever leave.

Alec:
It is my fire —
My one desire.

Nate:
Ph.D…
Andrew:
Ph.D…
Alec:
Ph.D…
Brock:
Ph.D…
Phil:
You never hear me!

All:
I’m ready for my thesis.
I could even do a defense.
I never wanna hear you say:
You’ll never graduate.

All:
Tell me when…
This stipend ain’t a salary.
Tell me when…
I wanna get better pay.
Tell me when…
You never wanna hear me say:
I want to graduate.

Nate:
Cuz I want to graduate…

Life here in the UC is much better than anything they got out there!

Members of the Drubin/Barnes Lab and others collaborated this month to create musical magic (or madness?) in the form a parody of the musical number “Under the Sea” from Disney’s The Little Mermaid.  The video was a submission for UC-Berkeley Department of Molecular and Cell Biology‘s annual funny movie event MCB Follies.

We hope you enjoy it!

CONCEPT: Akemi Kunibe

LYRICS: Eric Lewellyn

VOCALS: Nathaniel Krefman

BACKING VOCALS: Sun Hae Hong & Akemi Kunibe

CINEMATOGRAPHY: Akemi Kunibe, Jeff Woodruff, & Eric Lewellyn

EDITING: Jasper Weinberg & Akemi Kunibe

STARRING: Eric Lewellyn, Rebecca Lu, & Jasper Weinberg

CAST (in order of appearance): Rebecca Lu, Jasper Weinberg, Eric Lewellyn, Jeff Woodruff, Akemi Kunibe, Kathryn Sievert, Adrienne Greene, Sun Hae hong, Benjamin Gowen, Wendy Ingram, Kevin Barry, Caitlin DeJong, aileen Kelly, Caitlin Shartner, Christopher Alvaro, Jennifer Cisson, Nathaniel Krefman, Colin Cerretani, Thomas Burke, Julia Durack, Christina Glazier, & Michelle Reniere

________________________________________________

LYRICS:

Private industry, it’s a mess. Life here in the UC Berkeley is much better than anything they got out there.

The money is always greener,
In some private company.
You quit you could be a tech there,
But you would be sad you’ll see.
Just look at the world around you,
Right here through the lab room door.
Such wonderful things surround you.
What more is you lookin’ for?

In the UC!
In the UC!
Darling it’s better,
Grab your pipetter,
Come follow me!
Here you can surf for half the day.
With a real job you’ll slave away.
Ya we be chillin’.
Time we be killin’.
In the UC!

Right here all the postdoc happy.
They follow where research go.
The industry doc ain’t happy —
They feel like they sold their soul.
But doc with a job is lucky —
They in for a worser fate:
One day when the boss sell company,
Guess who eatin’ ramen plate!
Uh Oh!

In the UC!
In The UC!
We doin’ science.
We not some appliance,
for makin’ money.
They got a team of robots manned.
We got the Zen of workin’ by hand.
We got no worries,
Troubles or hurries,
In the UC!
In the UC!
Each protein gel here,
Runnin’ so well here,
Bands are so clean.
Even though takin’ lots of class,
Can be a real pain in the ass,
While we be learnin’,
money be earning,
In the UC!

The tub is the bass,
the drum is the flask,
the beakers are good,
for most any task.
Our science is play.
We do every day,
Like Nate, who’s the Duke of Clone.
Yeah!
He put DNA,
In cells on the plate.
The sequence is good.
There ain’t no debate.
Right here where it’s at,
Our microscope phat.
An’ oh that protein glow!

In the UC!
In the UC!
No scientist here,
Like to get pissed here,
You will agree.
We got a campus full a perks.
They got a boardroom full of rich jerks.
Each undergrad here,
Learning like mad here.
In the UC!
None of our tech here,
is pain in the neck here.
In the UC!
Each PI swell here.
Get the Nobel here.
Publish in Science,
Nature, and Cell here.
Stay academic.
The fun is pandemic!
In the UC!

Journal Club on Monday, October 15

For our Journal Club on October 15, Jay Ryoo presented the following paper:

The first five seconds in the life of a clathrin-coated pit. Cocucci E, Aguet F, Boulant S, Kirchhausen T. Cell. 2012 Aug 3;150(3):495-507. PMID: 22863004.

Schematic representation of the experimental setup and computational analysis