important memories

(Image caption: Images of mouse neurons from the hippocampal region of the brain. Levels of the surface receptor GluR1, orange, are shown in unmodified neurons, left, and in those with increased levels of Tet3, right. Credit: Huimei Yu, Johns Hopkins Medicine)

Neurons Constantly Rewrite Their DNA

Johns Hopkins scientists have discovered that neurons are risk takers: They use minor “DNA surgeries” to toggle their activity levels all day, every day. Since these activity levels are important in learning, memory and brain disorders, the researchers think their finding will shed light on a range of important questions. A summary of the study was published online in the journal Nature Neuroscience on April 27.

“We used to think that once a cell reaches full maturation, its DNA is totally stable, including the molecular tags attached to it to control its genes and maintain the cell’s identity,” says Hongjun Song, Ph.D., a professor of neurology and neuroscience in the Johns Hopkins University School of Medicine’s Institute for Cell Engineering. “This research shows that some cells actually alter their DNA all the time, just to perform everyday functions.”

This DNA alteration is called DNA demethylation. Methyl groups are regulatory tags that are permanently bound to cytosines, the C’s in DNA’s four-letter alphabet. Removing them is a multistep process that requires excising a tagged cytosine from the long string of paired “letters” that make up a chromosome and, ideally, replacing it with an untagged cytosine. Because the process involves making a cut into DNA, it leaves the DNA somewhat vulnerable to mutations, so most cells use the process sparingly, mostly for correcting errors. But recent studies had turned up evidence that mammals’ brains exhibit highly dynamic DNA modification activity — more than in any other area of the body — and Song’s group wanted to know why all this risky business was going on in such a vulnerable tissue as the brain.

The main job of neurons is to communicate with other neurons through connections called synapses. At each synapse, an initiating neuron releases chemical messengers, which are intercepted by receptor proteins on the receiving neuron. Neurons can toggle the “volume” of this communication by adjusting the activity level of their genes to change the number of their messengers or receptors on the surface of the neuron. When Song’s team added various drugs to neurons taken from mouse brains, their synaptic activity — the volume of their communication — went up and down accordingly. When it was up, so was the activity of the Tet3 gene, which kicks off DNA demethylation. When it was down, Tet3 was down too.

Then, they flipped the experiment around and manipulated the levels of Tet3 in the cells. Surprisingly, when Tet3 levels were up, synaptic activity was down; when Tet3 levels were down, synaptic activity was up. So do Tet3 levels depend on synaptic activity, or is it the other way around?

Another series of experiments showed them that one of the changes occurring in neurons in response to low levels of Tet3 was an increase in the protein GluR1 at their synapses. Since GluR1 is a receptor for chemical messengers, its abundance at synapses is one of the ways neurons can toggle their synaptic activity.

The scientists say they have discovered another mechanism used by neurons to maintain relatively consistent levels of synaptic activity so that neurons can remain responsive to the signaling around them. If synaptic activity increases, Tet3 activity and base excision of tagged cytosines increases. This causes the levels of GluR1 at synapses to decrease, in turn, which decreases their overall strength, bringing the synapses back to their previous activity level. The opposite can also happen, resulting in increasing synaptic activity in response to an initial decrease. So Tet3 levels respond to synaptic activity levels, and synaptic activity levels respond to Tet3 levels.

Song says: “If you shut off neural activity, the neurons ‘turn up their volume’ to try to get back to their usual level and vice versa. But they can’t do it without Tet3.”

Song adds that the ability to regulate synapse activity is the most fundamental property of neurons: “It’s how our brains form circuits that contain information.” Since this synaptic flexibility seems to require mildly risky DNA surgery to work, Song wonders if some brain disorders might arise from neurons losing their ability to “heal” properly after base excision. He thinks this study brings us one step closer to finding out.

Baby Princess is named in honour of her Grandfather, Grandmother and Great-Grandmother: Kate and William announce the very evocative names of their new daughter

After days of speculation, the baby’s name was announced by Kensington Palace this afternoon as Charlotte Elizabeth Diana (pictured centre). She will be known as Princess Charlotte of Cambridge. A princess called Charlotte - a name that is French in origin - is a nod to her grandfather, the Prince of Wales (inset), while Elizabeth and Diana are an obvious mark of respect to William’s 89-year-old grandmother (bottom right) and his late mother respectively (top right). In royal history, George IV named his only child Charlotte, but she died in childbirth at 21. George III’s wife was Queen Charlotte, who was born 1744. William has previously spoken of his deep respect for his father and the amount of time the prince commits to his charitable work. The Duke also places great importance on honouring her memory, having already used Diana’s sapphire and diamond engagement ring when he proposed to Kate (pictured together left). Royal aides told MailOnline that the baby’s second names were self-evident and would ‘speak for themselves’.

Source.

I don’t consider myself religious but tbh Virgin Mary was everywhere in my childhood and she is linked to very important and sweet memories of my grandparents and my country 

So if you dare to make fun of anything related to her I will stab you seven times in the heart in her name and I am sure that she will approve

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Hartwin AU

Where Harry Hart did not die, but was in fact de-aged by the bullet and comes back into Eggsy’s life as an adorable 23 year old man who turns out to be reckless, an absolute flirt, and–to Merlin’s utter chagrin–the epitome of being a little shit.

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The Memorial Challenge

I challenge you my loyal followers and friends, as well as each patriot, and fitness enthusiast to join me by doing pushup for every fallen US service member in the OIF/OEF conflict over the course of this next 365 days(April 23, 2016). That is 6,661 pushups to honor the fallen.

I will be taking things a step farther doing 1 pushup for every fallen US service member to have ever fallen over the course of this next 365 days(April 23, 2016). 1,171,177 pushups because I owe each of them a debt of gratitude and brotherhood.

I will be making weekly updates to any and all interested under the tag “veteranblr memorial”

I tried to recover some very important memories of my childhood. When I found an isolated and condensed memory in my mind, I wrote it down—I discovered very quickly that as soon as I did that, I lost it. I didn’t lose it exactly, but when I tried to find it again, what I found was what I had written. You see, it’s exactly like when you are on the beach and you take a very pretty pebble that’s been in the water and it’s brilliant and then it dries up and there’s a film of salt over it and it’s not beautiful anymore—it’s finished. The gleam of it, the light of it, is gone! As for memories, it’s exactly the same. By working like this I destroy my memory… I wanted to destroy my memory, because of some sadness in it.
—  Jacques Roubaud

You once told me that you found me to be extraordinary. You once laid beside me and spoke about how my mind was unusual; that’s why you loved it—[me]. You once spoke about how I filled you with endless possibilities and how you made a home in my chaos. You once said that my free-spirited nature was going to be the death of you—that the way I looked at you made you choke on my name when it left your tongue. You once whispered how you would miss me if I were to ever leave you. You once loved me.

But the very qualities you loved, you grew to resent. And so winter turned to spring, and when I woke up to the sun in my face, I saw only one shadow residing on the wall. And then you were gone. It turns out that I wasn’t the death of you—you were the death of me.

—  Kelsey Gustafsson

so last summer one of my roommates put “frozen peas” on a shopping list and the other roommate took the list and went out to a bulk store and bought a FIVE-POUND BAG of peas. & roommate #1 used like half a cup of peas and left the rest in the freezer! and over the past, like, ten months, we have just continued to slowly chip away at the peas, but at some point the bag broke and it just got worse and worse. so today i went to get some peas to put in fried rice and came to realize that we just had like a three-pound block of frozen solid freezer-burned peas hanging out in the freezer? so we decided finally that it was time to throw away the peas but now there is this mass of peas kind of shaped like some kind of animal head slowly and horrifically melting in the trash can

the sunshine family | naruto

prompt: This post by the lovely sakaeguchiyuuto  ( ´ ▽ ` )ノ

pairing: The sunshine family. 

notes: I’m so happy I’m writing this, the fanart was so cute and I’m so inspired by fanart everyday when I write because everything you artists do is just simply astonishing. And thank you sakaeguchiyuuto for letting me put a cute family story to your art! I hope everyone enjoy this short little fic. And I hope I did it justice. Enjoy!


Family bonding is important, it makes memories, lasting bonds, and most importantly love grows. Love is the ingredient that holds families together, and makes them stronger. And the love of a family can never wilt.


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when I was a little kid I wrote these one-page stories called Batcat and Supercat, and honestly I don’t know why I felt compelled to do this or where I got my information because I never actually cared or knew anything about superheroes other than their names

I guess I just knew they were a thing and therefore to my sensible child brain could be made into cats

story time ok so one time in like 8th grade i lost my necklace when we were playing flag football in gym and of course i checked everywhere even my clothes and bra but then later i was eating chips and dropped one in my bra but instead of a chip i pulled out the necklace and never found the chip

Buddy Birthday List

Heya there, sweetiepies!

So, as some of you may probably already know, I have a veeeery terrible memory. Dates are especially difficult for me to keep track of ! Thus, to apply on Tumblr the same thing I do with friend outside of the Internet, here is before y'all the Buddy-Birthday list post ! Basically, I would just ask of you to send me/comment on this post you lovely people’s birthday dates so I don’t forget them <3. There’s some of yours that I don’t even know yet !

Not a mutual but you would enjoy having another birthday wish in your askbox nethertheless? No problem! Feel free to drop in your bday-date as well! I’d be super happy to send you wishes ! You don’t want your birthday date to be publically posted? That’s tots fine, dearie! There’s no obligation at all! You hate your birthday date?? I will try to remove it from the calendars even if I have to be banned from airplanes !!

I’m just gonna go ahead and put in the ones I already know and update it over time in alphabetical order! Don’t be shy, ask awaaay !! ~~ 

cipherking : June 21st  
funkyhunkygrunklestans : August 15th
honeywaspkittenbaby : November 27th 
insane-dorito :  February 5th
jimsdeadbones : April 23rd
moonturtle6 : April 9th
shootingstarrod : January 22nd
zimiestef​ : January 1st

“You never know the true value of a moment until it becomes a memory.”

“You never know the true value of a moment until it becomes a memory.”

The morning is chilly, but the sun is shining which gives hope for a warmer day. Rain is coming maybe tonight but definitely tomorrow. I love this time of year when my world is wonderfully spring green.

This morning I realized I know too many useless facts. They are taking up space in my memory drawers, and they don’t seem to have much value beyond a bit of cocktail chatter. Who really cares that…

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