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We've all learned that neurons are one of the main building blocks of your brain.
我們都知道，神經(jīng)元是大腦的主要組成部分之一。
They shuttle along information so you can think and feel and remember and do things.
它們往來(lái)傳遞信息，這樣你就能思考、感覺(jué)、記憶與做事了。
Neurons communicate with each other using chemicals called neurotransmitters,
神經(jīng)元用于相互交流的化學(xué)物質(zhì)叫做神經(jīng)遞質(zhì)，
which get passed through a gap called a synaptic cleft.
后者能通過(guò)突觸間隙。
Now, this way of communication has been the basis for a lot of research into brain chemistry,
現(xiàn)在，這種交流方式已經(jīng)成為眾多腦化學(xué)研究的基礎(chǔ)，
and it has massively influenced how we design medicines that target the brain.
極大地影響著我們針對(duì)腦部的藥物研究設(shè)計(jì)。
But scientists have observed a new way that neurons can pass information.
但是科學(xué)家們注意到了一種神經(jīng)元傳遞信息的新方式。
It's pretty groundbreaking… and it's pretty weird.
它非常具有開(kāi)創(chuàng)性，而且很奇怪。
All this excitement centers around the Arc gene.
所有這些興奮發(fā)現(xiàn)都是關(guān)于Arc基因的。
Like many genes, it encodes a string of mRNA which encodes a protein.
Arc基因與許多基因一樣，它編碼一連串能編碼蛋白質(zhì)的信使核糖核酸（mRNA）。
And Arc has been studied in relation to memory and learning.
研究表明，Arc與記憶和學(xué)習(xí)有關(guān)。
After a neuron fires, which is when an electrical signal gets sent through the cell,
神經(jīng)元被激活后，即電信號(hào)通過(guò)細(xì)胞發(fā)出后，
the Arc protein and mRNA build up in the cell's dendrites.
Arc蛋白和mRNA在細(xì)胞的樹(shù)突中形成。
These are the branches that connect one neuron to others,
樹(shù)突是連接一個(gè)神經(jīng)元與其他神經(jīng)元的分叉，
usually by receiving neurotransmitters.
通常接收神經(jīng)遞質(zhì)。
Arc's full name is activity-regulated cytoskeleton-associated protein,
Arc的全名叫做活性調(diào)節(jié)的細(xì)胞骨架相關(guān)蛋白，
because it's involved in changing a neuron's cytoskeleton,
因?yàn)樗鼌⑴c改變神經(jīng)元的細(xì)胞骨架,
the network of proteins that gives cells their structure.
細(xì)胞骨架是指形成細(xì)胞結(jié)構(gòu)的蛋白質(zhì)網(wǎng)。
We think this helps reinforce connections between neurons, which helps us hold on to information.
我們認(rèn)為它有助于加強(qiáng)神經(jīng)元之間的聯(lián)系，幫助我們保持信息。
Stronger connections mean stronger memories.
聯(lián)系更強(qiáng)意味著記憶更強(qiáng)。
And without the Arc gene, we might not be able to remember new things as easily.
沒(méi)有Arc基因，我們可能無(wú)法輕易記住新事物。
In a study from 2000, researchers conducted some experiments involving the Arc gene in rats.
在2000年的一項(xiàng)研究中，研究人員用攜帶Arc基因的老鼠進(jìn)行了一些實(shí)驗(yàn)。
They used 42 male rats, half of which were dosed with a compound that messed with Arc mRNA
他們使用了42只雄鼠，其中一半服用了含Arc信使核糖核酸的化合物，
and kept them from making proteins.
并阻止它們制造蛋白質(zhì)。
The other half got a control dose that didn't affect Arc.
另一半服用了不影響Arc的控制試劑。
After the brain treatment, the rats were trained to find a hidden platform in a tank filled with water.
經(jīng)過(guò)大腦治療，老鼠們被訓(xùn)練在裝滿水的水箱里找一個(gè)隱藏的平臺(tái)。
All the rats did fine after a couple practice rounds, Arc protein or not.
不管有沒(méi)有Arc蛋白質(zhì)，所有的老鼠在經(jīng)過(guò)幾輪訓(xùn)練后都表現(xiàn)良好。
But then, 48 hours later, they were all tested on their ability to find the platform again.
但是48小時(shí)后，他們又被測(cè)試再次找到平臺(tái)的能力時(shí)，
And rats that had the Arc-inhibiting dose in their brains did worse than the control group,
那些大腦中有Arc抑制劑的老鼠比對(duì)照組表現(xiàn)的糟糕，
which the researchers took to mean that they had trouble forming memories of the practice.
研究人員認(rèn)為，這意味著它們很難形成對(duì)這種訓(xùn)練的記憶。
In a separate experiment, they tried dosing rats with the compounds 8 hours after the training session.
在另一項(xiàng)實(shí)驗(yàn)中，研究人員在訓(xùn)練結(jié)束8小時(shí)后給老鼠服用了混合試劑，
And both groups of rats did about the same on the test!
結(jié)果兩組老鼠在實(shí)驗(yàn)中表現(xiàn)相同！
So this makes Arc seem especially important while the rats were learning the task and forming those neural pathways.
因此實(shí)驗(yàn)表明，當(dāng)老鼠學(xué)習(xí)任務(wù)并形成這些神經(jīng)通路時(shí)，Arc顯得尤為重要。
Now, this bit of research in itself is neat.
這項(xiàng)研究本身很巧妙。
But Arc is also interesting in human brains, even though we're not entirely sure what it's doing.
但是人類(lèi)大腦中的Arc也很有趣，盡管我們并不完全確定它的作用。
Abnormal levels of Arc protein have been found in patients with Alzheimer's disease.
我們發(fā)現(xiàn)，阿爾茨海默病患者體內(nèi)的Arc蛋白水平異常。
And studies with genetic analyses have suggested that Arc gene variants may play a role in schizophrenia.
而且遺傳分析研究表明，Arc基因變異可能在精神分裂癥中起作用。
And then there's the Arc research that's changing how scientists think about brains altogether.
隨后Arc的研究改變了科學(xué)家們對(duì)大腦的看法。
In a paper published in January 2018 in the journal Cell,
在2018年1月發(fā)表于《細(xì)胞》雜志上的一篇論文中，
researchers from the University of Utah described their most recent work on the Arc gene,
猶他大學(xué)的研究人員描述了他們最近在Arc基因上的研究，
when things took an unexpected turn.
這時(shí)事情出現(xiàn)了意外轉(zhuǎn)機(jī)。
The first big surprise was when they looked at some engineered bacteria
第一個(gè)大驚喜是，他們?cè)谘芯恳恍?/div>
that were churning out Arc proteins from a rat gene.
大量制造由老鼠基因產(chǎn)生的Arc蛋白的工程菌時(shí)，
They noticed that Arc was clumping up into structures that looked weirdly like capsids,
注意到，Arc聚集成看起來(lái)很怪的衣殼結(jié)構(gòu)，
tiny protein capsules that protect the genetic information of viruses.
衣殼是指保護(hù)病毒遺傳信息的微小蛋白膠囊。
Not only that, but more tests showed that
不僅如此，更多的測(cè)試表明，
Arc capsids form little packages around Arc mRNA and other RNA that might be hanging out in cells.
Arc衣殼在其mRNA以及常進(jìn)細(xì)胞的其他核糖核酸（RNA）周?chē)纬尚“?/div>
Which is also like viruses.
這也和病毒一樣。
Then, the scientists tried sticking the Arc proteins in a bunch of mouse neurons
然后，科學(xué)家們嘗試在一堆老鼠神經(jīng)元中加入Arc蛋白質(zhì)，
and noticed that capsids were actually shuttling mRNA between cells.
并注意到，衣殼實(shí)際在細(xì)胞之間運(yùn)送mRNA。
And with the extra mRNA, the receiving neurons could probably generate even more Arc.
接收神經(jīng)元利用多余的mRNA可能會(huì)產(chǎn)生更多的的Arc。
That's what had researchers floored: Arc capsids crossed synapses.
這就是研究人員的研究成果：Arc衣殼能穿過(guò)突觸。
They carried information between neurons in a way that we thought was exclusive to neurotransmitters!
它們用一種我們之前認(rèn)為獨(dú)屬于神經(jīng)遞質(zhì)的方式在神經(jīng)元之間傳遞信息！
And after some genetic analyses, they think that the Arc gene doesn't just act like a virus…
研究人員在進(jìn)行一些基因分析之后認(rèn)為，Arc基因并不像病毒一樣……
Hundreds of millions of years ago,
幾億年前，
it probably came from a retrovirus ancestor that infected our ancestors and got into our genome.
它可能是感染了我們祖先的逆轉(zhuǎn)錄酶病毒祖先，并進(jìn)入了我們的基因組。
Now, having virus genes stick around in your body might sound a little risky
現(xiàn)在，讓病毒基因留在身體里聽(tīng)起來(lái)有點(diǎn)兒冒險(xiǎn)，
I mean, that's the huge problem with HIV.
我的意思是，這是攜帶HIV病毒的一大問(wèn)題。
But some estimates suggest that up to 8% of human DNA could've come from retroviruses.
但一些估計(jì)顯示，多達(dá)8%的人類(lèi)DNA可能來(lái)自逆轉(zhuǎn)錄酶病毒。
Most of this DNA has changed enough that it doesn't do anything.
這類(lèi)DNA大部分已經(jīng)改變了，沒(méi)什么危害。
But some researchers have argued that certain viral fragments have been repurposed by our bodies.
但一些研究人員認(rèn)為，某些病毒碎片已被我們的身體重新利用了。
And now with Arc, we aren't sure how or why our neurons seem to be using these virus-like capsids.
有了Arc的例子，我們不確定神經(jīng)元為什么使用這些病毒一樣的衣殼。
Not to mention, they're not just in the brain.
更不用說(shuō)它們不僅存在于大腦中了。
In a separate paper published on the same day in the same journal,
在該雜志同一天發(fā)表的另一篇論文中，
researchers from the University of Massachusetts reported on Arc capsids crossing synapses in fruit flies.
來(lái)自馬薩諸塞大學(xué)的研究人員報(bào)告稱(chēng)，果蠅中有Arc衣殼穿過(guò)突觸。
But in these experiments they were crossing the neuromuscular junction,
在這些實(shí)驗(yàn)中，它們正穿過(guò)神經(jīng)肌肉接點(diǎn)，
where neurons and muscles meet.
即神經(jīng)元和肌肉的交匯點(diǎn)。
So it seems like Arc could be involved in connections here, too. Not just between neurons.
所以Arc似乎也與這里的連接點(diǎn)有關(guān)。不只是在神經(jīng)元之間。
All these findings are still really new, so scientists have a lot more questions than answers.
這些發(fā)現(xiàn)仍舊都是新的，所以科學(xué)家們有了更多的疑問(wèn)，而不是答案。
We still don't really know how this virus-like communication strategy affects memory,
我們?nèi)匀徊恢肋@種病毒式的傳播策略是如何影響記憶的，
or even what else could be ferried around by Arc capsids.
或者有什么其他東西被Arc衣殼包裹著運(yùn)輸。
Like, what if they help toxic proteins move around the brain,
比如，如果它們能幫助有毒蛋白質(zhì)在大腦中移動(dòng),
which is a major problem with Alzheimer's disease.
那么它將成為阿爾茨海默病的一個(gè)主要問(wèn)題。
So first, researchers studying Arc want to try and repeat these observations.
因此，研究Arc的研究人員首先想嘗試并重復(fù)這些觀察。
And then they'll keep experimenting,
接著，他們會(huì)繼續(xù)實(shí)驗(yàn)，
looking in mammals instead of isolated cells or flies to try and find these Arc capsids in action.
通過(guò)觀察哺乳動(dòng)物而不是孤立的細(xì)胞或蒼蠅，試圖找到這些活動(dòng)中的Arc衣殼。
Some scientists think this could open up a new door in treating brain-related illnesses in humans.
一些科學(xué)家認(rèn)為，這將為人類(lèi)治療腦相關(guān)疾病打開(kāi)一扇新的大門(mén)。
Instead of drugs that target neurotransmitters,
也許，我們終有一天不用研制針對(duì)神經(jīng)遞質(zhì)的藥物，
someday we may be able to use Arc capsids to smuggle helpful stuff directly into neurons
能夠使用Arc衣殼將有益物質(zhì)直接帶入神經(jīng)元，
and that would be pretty revolutionary.
而這相當(dāng)具有革命性。
Thanks for watching this episode of SciShow Psych!
感謝您收看本期的心理科學(xué)秀！
And if you want to learn more about memory,
如果你想了解更多關(guān)于記憶的內(nèi)容，
you can check out our other videos on this channel,
可以查看這個(gè)頻道的其他視頻，
like one where we explain whether photographic memory really exists.
比如其中一個(gè)解釋了過(guò)目不忘的能力是否真得存在。
| 重點(diǎn)單詞 | 查看全部解釋 | |||
| bacteria | [bæk'tiəriə] |
想一想再看 n. (復(fù)數(shù))細(xì)菌 |
||
| unexpected | ['ʌnik'spektid] |
想一想再看 adj. 想不到的，意外的 |
||
| exclusive | [iks'klu:siv] |
想一想再看 adj. 獨(dú)占的，唯一的，排外的 |
聯(lián)想記憶 | |
| genetic | [dʒi'netik] |
想一想再看 adj. 基因的，遺傳的，起源的 |
聯(lián)想記憶 | |
| ancestor | ['ænsistə] |
想一想再看 n. 祖宗，祖先，原種 |
聯(lián)想記憶 | |
| episode | ['episəud] |
想一想再看 n. 插曲，一段情節(jié)，片段，軼事 |
聯(lián)想記憶 | |
| platform | ['plætfɔ:m] |
想一想再看 n. 平臺(tái)，站臺(tái)，月臺(tái)，講臺(tái)，(政黨的)政綱 |
聯(lián)想記憶 | |
| abnormal | [æb'nɔ:məl] |
想一想再看 adj. 反常的，不正常的，不規(guī)則的 |
聯(lián)想記憶 | |
| protect | [prə'tekt] |
想一想再看 vt. 保護(hù)，投保 |
聯(lián)想記憶 | |
| tank | [tæŋk] |
想一想再看 n. 坦克，箱，罐，槽，貯水池 |
