Getting a handle on the O-GlcNAc modification

Protein glycosylation is usually relegated to the cell surface and intracellular compartments. In a fascinating exception to this rule that was first observed in the 1980's, A GlcNAc monosaccharide can be added to serine and threonine residues of cytosolic proteins. Many labs are trying to understand the dynamic regulation of the addition and removal of this sugar that seemingly has a hand in every cellular process and disease state known to man. More and more examples are being found to suggest that this modification and phosphorylation regulate each other, as if they weren't already complicated enough on their own.

There are a handful of ways to detect O-GlcNAc, which have helped build the laundry list by telling us which proteins are modified. Now, in a recent Nature Chemical Biology paper from Linda Hsieh-Wilson's lab at CalTech, they show us a useful new method that reveals what proportion of any particular protein is modified (2%? 80%), and of those that are modified, exactly how many GlcNAc residues there are per protein. They do this by adding a great big heavy tag (polyethylene glycol) to the modification, which makes the protein sluggish on a polyacrylamide gel. Proteins that have been modified then resolve as separate slower-moving bands on the gel according to how many GlcNAc residues adorn them.  I made the illustration above for a highlight of the paper that will appear in the Functional Glycomics Update, a collaboration between the Consortium for Functional Glycomics and the Nature Publishing Group. The image will be much smaller than you see here, which is why I took kind of a loose style for the protein, playing around with the paint brush tools in Illustrator. I haven't actually decided whether I like it or not, but this is where I am with it.

Look at me, playing the lute in a Caravaggio painting

This was my homework for my Photoshop class this week.

Scenes from Indianapolis airport

Just got back from a brief but fun trip to my hometown to visit family and friends. Airports are great places to sketch. People are preoccupied, but at the same time relatively still, since we spend most of the time there waiting. For a couple of these sketches I even had 5 minutes or more before the pose shifted or they left to board a flight. As far as I could tell, no one noticed me drawing them. (Beware of creepy airport sketchers!) Once I got caught doing this in a Starbucks. My subject started striking poses worthy of a Madonna video, totally embarrassing me.

Bar code series

Okay, the truth is I've just been tying up loose ends over the past couple of days and I don't have anything new and exciting to share. This was an assignment I did several months ago for an illustration course. We were given words or phrases and told to illustrate them while somehow incorporating a bar code. Here is what I came up with for anatomy, architecture, games, music, and red light district.

Latest installment of chemistry poetry illustrations

As I mentioned before, one of my ongoing projects is to illustrate poems about chemistry that were written by an old classmate of mine so she can publish her collection.  Here are some sketches I did in Illustrator (after doing many many versions of them with pencil and paper).  Ultimately I'll do them in pen and ink with ink wash, which is why they are not in color.

The first one deals with kinetics. No matter how thermodynamically favored the romance between these star-crossed reactants may be, they need to find each other to react. The middle sketch is for a poem about neon gas, and the laws to which it must adhere. And finally, this tortured barium dreams of breaking free of his latticed prison and the loveless marriage to two fluorine atoms. Sadly, his hopes for solubility are dashed by the common ion effect.

Old chair, new chair

Got a new chair this week.

Crayons, please?

Since I was thinking about the project I had lined up for the weekend, I did this rough sketch on a white board at husband's workplace while waiting for him to finish up on Friday evening. So, apparently I am seven. On the bright side, I did not get fussy.

Update on Monday, August 9, 2010 at 11:38AM by Mary

And here is the result:

Cover Me!

I'm about to submit a manuscript to a journal that invites authors to send in possible cover art with initial submission of the manuscript. Here's a mock-up. I took into account the placement of the title, which is why there's some empty space. I'll be happy just to have the paper accepted, but wouldn't mind getting the cover too! It's about our discovery that the cell surface receptor CD22 recycles back to the cell surface after endocytosis, and that it differentially transports cargo into the cell, depending on the cargo. Fingers crossed!

Update on Thursday, December 2, 2010 at 05:19AM by Mary

Paper accepted today in Journal of Immunology! Hooray! (Still have to wait to see if they use the cover)

Update on Friday, January 14, 2011 at 11:26AM by Mary

Of all the lousy luck, someone publishing in the same issue had a scanning electron microscopy image of a macrophage phagocytosing red blood cells, and it is awesome. I totally would have chosen that over mine too.

Brushing up on a different medium

Sorry, I couldn't resist the punny title. This weekend I've been playing around with using pen and ink with an ink wash on watercolor paper for some illustrations.  Here are a couple of prototypes in progress.

Tribute to Husband

It's about time I give some credit to the source of many of the human forms I use in my drawings - my husband. He's always willing when I need to snap a reference photo to capture a pose, or even just an ear, like this:

He doesn't even ask what it's for, he's just happy to help. The best part is, he's funny. When I asked him to help me simulate the heimlich manuever, I had no idea that he was going to look straight into the camera with such a look of deep concern. I laughed the entire time I drew this:

Sometimes he requests that I change his appearance so that he is not recognizable, and I oblige.

Whether it's for a column in the AWIS magazine

or an assignment for my graphic design class

he never complains. As if it weren't enough that he is extraordinarily supportive of my "alternate career" or "career away from the bench" or whatever the kids are calling it these days, he is always behind the scenes with a keen eye for design. He is the one who reins me in when I want to write a line of text in the shape of an elephant just because I learned how to use the type on path tool in Illustrator. Plus, he knows all of the lyrics to Pinball Wizard. I'm a lucky lady, I am.

A Few Good Women

Here's an infographic I made yesterday for the next issue of the Association for Women in Science's quarterly magazine, the theme of which is Leadership. The statistics come from articles going into the issue, and are meant to highlight the relative dearth of female role models in leadership positions. I suppose I must be one of the lucky ones, because I have had no shortage of outstanding female role models throughout my entire training. 

Perspective on glycan arrays

I put this figure together this week for a review being published from my lab about glycan arrays. They wanted to convey that a wide variety of glycans is spotted on the array, and also that each spot displays a multivalent presentation of these glycans. Multivalency is important to capture the glycan-binding proteins (right) and viruses (left) that are routinely screened by this method. This was also an attempt to conform to the style of the journal to which it's going. You know, so I'm like versatile and stuff. But mostly I enjoyed invoking the old 1-point perspective lines, which always reminds me of my 6th grade art class, where we drew our names in block letters and then used 1-point perspective to make them 3D. It blew my 11-year old mind.

Masked microbes

Some pathogenic bacteria have a clever strategy for evading our innate immune system - make themselves look like our red blood cells. Our immune system has been programmed to not attack our own cells, for obvious reasons. These wily bacteria come decorated with our blood group antigens (the carbohydrates that govern our blood type). The illustration below shows their attempted masquerade. But the Cummings group has found that we may be one step ahead. In Stowell SR, et al. “Innate immune lectins kill bacteria expressing blood group antigen.”  Nature Med. 2010 16, 295-301, they show that we express two isoforms of the glycan-binding protein known as galectin to kill the bacteria by recognizing the blood group antigen. Presumably, by selectively expressing them in the intestinal epithelium, they won't bother our red blood cells. 

Chemistry and Art meet at the historic Hollywood Bowl

When fuel and oxidizers meet elements like sodium, barium, copper and lithium, we get fireworks. Throw in a John Philip Sousa march by the LA philharmonic and you have one great spectacle.

Drug screening

My Mini-Muse

My best friend has a 3-year old daughter. I was in the hospital when she was born. I held her as she looked up at me with gooey little eyes. So overcome with adoration was I, that I decided to paint a portrait of her for each of her birthdays. I realize now that it may be somewhat ambitious, that she may not want a stack of portaits of herself. I don't even like seeing photos of myself from the "awkward stage" (roughly ages 7-23, in my case). But for now, while she is fast growing, unbearably cute, and wonderfully expressive, I am working on the third painting in the series. Here it is at an early stage.

Finding Amino

Here is a rough sketch of another chemistry poem illustration in the works. The poem is about a very distraught protein looking for its lost N-terminal glycine residue, named Amino.

Here is a logo and graphic that I put together for my friend Nicole's blog, The Concentric Circle, which launched this week. She is an extremely talented journalist who now spends her days editing other people's writing.  Like the professor who yearns to do experiments with his or her own hands again, Nicole felt an urge to get back to writing, and thank goodness for that. It is an absolute joy to read.

The Original Heidelberg Monster

I recently had the opportunity to visit a printing company in San Diego. I learned how terribly things can go wrong when preparing files for print and how the nice employees will feel about me when it happens. I imagined that they keep this old Heidelberg printing press (see photo) for the express purpose of feeding it designers who don't know the difference between CMYK and RGB, or don't manage their fonts properly. I had at least three panic attacks as it just so happened that one of my projects had just been sent to the printer and my client was awaiting the proof.  I saw my fate in the second photo below if the file wasn't prepared properly.

There once was an atom of tin . . .

I've recently embarked on a very exciting collaboration with a classmate from MIT - to illustrate her chemistry poetry.  Just to get the ball rolling, I took a stab at one of my favorites. Here is a draft. The poem is about a tin atom trying to get into Club Atomic. The snooty bouncer explains that elements are admitted by the gram, and letting him in would exceed the tin allowance. Tin explains that this gives an unfair advantage to the lighter elements, such as the helium atoms filing in, and he finally convinces the bouncer that elements should be admitted by moles, or number of atoms, not by weight. 

Update on Saturday, June 26, 2010 at 05:15PM by Mary

Back to the drawing board!