(Image caption: Using postmortem human brains and human embryonic stem cell models of brain development, Salk Institute researchers discover a new mechanism to generate DNA variation in human neurons. Here, human embryonic cell- derived neurons stained for a neurons specific marker (Tuj1, green, DNA show in red) show remarkable diversity. Credit: Salk Institute)

The brain’s stunning genomic diversity revealed

Our brains contain a surprising diversity of DNA. Even though we are taught that every cell in our body has the same DNA, in fact most cells in the brain have changes to their DNA that make each neuron a little different.

Now researchers at the Salk Institute and their collaborators have shown that one source of this variation—called long interspersed nuclear elements or L1s—are present in 44 to 63 percent of healthy neurons and can not only insert DNA but also remove it. Previously, these L1s were known to be small bits of DNA called “jumping genes” that copy and paste themselves throughout the genome, but the researchers found that they also cause large deletions of entire genes. What’s more, such variations can influence the expression of genes that are crucial for the developing brain.

The findings, published September 12, 2016 in the journal Nature Neuroscience, may help explain what makes us each unique—why even identical twins can be so different from one other, for example—and how jumping genes can go awry and cause disease.

“In 2013, we discovered that different neurons within the same brain have various complements of DNA, suggesting that they function slightly differently from each other even within the same person,” says the study’s senior investigator Rusty Gage, a professor in Salk’s Laboratory of Genetics and holder of the Vi and John Adler Chair for Research on Age-Related Neurodegenerative Diseases. “This recent study reveals a new and surprising form of variation that will help us understand the role of L1s, not only in healthy brains but in those affected by schizophrenia and autism.”

In 2005, Gage’s team discovered L1s as a mechanism of genome diversity in the brain. However, it was not until it became possible to sequence the entire genome of a single cell that scientists could get a handle on the amount and nature of these variations. Using single-cell sequencing detailed in a 2013 Science paper, Gage’s group showed that large chunks of DNA were inserted—or deleted—into the genomes of the cells.

(Image caption: The “jumping gene” L1 cuts DNA in human cells to generate neuronal genomic diversity. Cells expressing L1 (genomic DNA shown in red) have high levels of DNA breaks as visualized by 53BP1 staining (green) which repairs broken DNA. Credit: Salk Institute)

But even in that study the mechanisms responsible for causing insertions and deletions were unclear, making it difficult to decipher whether specific regions of the genome were more or less likely to be altered, as well as whether jumping genes were related to the deletions.

In the new study, Gage, co-first authors Jennifer Erwin and Apuã Paquola, and collaborators developed a method to better capture the L1-associated variants in healthy neurons for sequencing and created a computational algorithm to distinguish the variations with greater accuracy than before.

Using stem cells that are coaxed to differentiate into neurons in a dish, the team found that L1s are prone to DNA breaks. That’s because a specific enzyme that chews through L1 spots in the genome is particularly active during differentiation. People inherit some L1s from their parents, and the enzyme appears to cut near these spots, the group found.

“The surprising part was that we thought all L1s could do was insert into new places. But the fact that they’re causing deletions means that they’re affecting the genome in a more significant way,” says Erwin, a staff scientist in Gage’s group.

Gage believes that diversity can be good for the brain—after all, about half of our brain cells have large chunks of missing or inserted DNA caused by L1s alone—but that too much of it can cause disease.

Recent evidence has shown that neurons derived from individuals with schizophrenia or the rare autism-associated disorder Rett syndrome harbor more than normal amounts of L1 variations in their genomes. In the new study, the team examined a schizophrenia-associated gene called DLG2, in which introducing L1 variations can change the gene’s expression and subsequent maturation of neurons. The group plans to explore the role of L1 variations in other genes and their effects on brain activity and disease.

anonymous asked:

the theme colors are a bit bright when looking at night, and the desktop font is a bit small but other than that it looks great!

Yeah i think its cuz the header right now doesnt have an image, I’m going to pick one out but im having trouble deciding :/ Thank you for the feedback!!!  ♥

i love how horikoshi is handling bakugou’s development…we see him mellow out in small bits over time but always constantly faced with his internal pride and arrogance that he’s better than izuku…but now izuku is pushing farther and farther ahead than he feels he himself is. that was just ending with bakugou being bitter but then all might loses his power and he’s at breaking point because he thinks he was the one to push it over and cause his hero’s downfall AND izuku is the one acknowledged by all might and bakugou knows izuku is at equal par with him or even more. and now this is possibly going to be the part where he goes past all that (or alternately becomes sasuke but i trust horikoshi to give me a bakugou that takes midoriya’s hand when he asks if he’s alright in some time if he’s not dead from that 8% smash)

Dear my next best friend,

Please come. I’m getting desperate. Everyone else is always posting Facebook photos of them and their friends and I barely even have acquaintances. I’m really bad at making friends, I’m not good at the small talk bit. I’ve been trying to talk to more people, but I’m usually left on read.

Can you just show up in my life already? I’m way past ready for you. I’m so ready to make a Pinterest board of cheesy quotes that remind me of our friendship. We’ve just gotta become friends first.


december 7, 2016

been doing really well the past few days!! not mentally, mentally I’ve been absolute shit. but eating-wise, I’ve been doing really well!!
all I ate yesterday was a banana and a few pieces of broccoli. today I went for a half hour walk, and ate a banana, a few pieces of pineapple, one piece of cantaloupe, a small bit of fat-free yogurt, and a handful of nuts. been trying not to eat nuts buuut I had the last of them just now so I won’t be having any more!!
I honestly haven’t even been hungry, like at all, and the only reason I ate was basically to show my family that I am eating, which is a poor excuse and I should’ve just fasted.
tomorrow I have my first therapy sesh since I came clean about how I haven’t been doing well and don’t want to recover, and I also have my first psychiatrist appointment ever. so I’m terrified 🙃

Actual Things I've Called My Faves sentence starters
  • "Precious bean"
  • "Self hating cinnamon roll"
  • "Actual heap of garbage"
  • "Badass bitch queen"
  • "My cinnamon son"
  • "Type A extrovert"
  • "That one kid who reminds the teacher that homework was due"
  • "Kind of an alcoholic"
  • "Well intentioned asshole"
  • "Full blown psychopath, probably"
  • "My precious kickass daughter"
  • "The ultimate cinnamon bun"
  • "A jackass, but only to ________"
  • "Huge awkward nerd"
  • "Small angry bean"
  • "A literal can of whoop ass"
  • "The kind of person who uses minion memes unironically"
  • "The Mom Friend™"
  • "One of the worst people you'll meet"
  • "Hopelessly romantic beanpole"
  • "A cinnamon roll but if you accidentally used too much baking powder and now it tastes like nothing but salt"
  • "A salt miner"
  • "Talk shit get hit, then hit again"
  • "A very small good, a very good small"
  • "A bit of a coward"

anonymous asked:

Can a person be pan (romantic/sexual) but with a small preference? Like, "Sarah is pansexual and likes all genders, but she likes girls a small bit more than guys and other genders". Is that still pan?

Basically there are two definitions of pan. One is “attracted to people regardless of gender” or “without a preference for a specific gender”, so according to that definition it isn’t.

However, the other definition that many pan people use is simply “attracted to people of all genders” so yes, you can use it.

Mod Raccoon

Me: I think I’m going to study in the library tomorrow.

Stepmom: What? Is the house not good enough for you?

Me: It’s a bit small and I like studying around other people. Such as in public libraries or at parties.

Stepmom: Why?

Me: Well just as it’s easier to fight against a shared enemy rather than for an ideal, it’s easier for me to focus on reading something not immediately pleasurable when I’m *actively ignoring* someone.
Celeb Pick 'Em with Eddie Kaye Thomas
Actor Eddie Kaye Thomas makes his picks for NFL week 14.

EKT talks baseball (mostly), “american pie” & “scorpion”

EKT: It’s a really insane, ridiculous show. (on Scorpion.)


PS. Do not watch/listen to the end of the video/clip if you do not want spoilers. He gives small spoilery bits about the cases & things that happen in several season 3 episodes - from 3x09 to 3x14 and 3x15. And you’ll know too much about the popcorn related event in episode 310 if you watch…as there’s a small sneak peek clip from the teaser of ep 310 with the doc & Walt. 

i know it’s hard to accept compliments as anything other than lies. but when somebody blurts, “you’re beautiful,” take a breath. think of your dog, panting happily and covered in mud. think of your mother in her bathrobe with her hair in tinfoil while the dye sets. think of your best friend with her face streaked with tears and makeup. think of your little brother when he was sick and his face was a red puffy mess. think of how, even then, your heart swelled up with love of them. this is i think where compliments come from: when they look at you, no matter what, they see somebody beautiful, not some body, beautiful.


Sterek AU: Drive-Thru I Do’s

Stiles finally cracks. He’s had enough of this town and not enough of Derek. They’ve secretly, well as secretly as you can be with a bunch of weres around, carried on their long distance relationship for over a year now while Derek took his pack to mingle with others across the world. Now Stiles wants nothing more than to finally be with his Alpha-hubby-to-be and his pack, their pack, for as long as they both shall live.


                                                      Isn’t Tsukiyama also like that?