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DNA tape recorder stores a cell’s memories

first_imgIf cells could talk, they’d have quite a story to tell: Their life history would include what molecules they’d seen passing by, which signals they’d sent to neighbors, and how they’d grown and changed. Researchers haven’t quite given cells a voice, but they have now furnished them with a memory of sorts—one that’s designed to record bits of their life history over the span of several weeks. The new method uses strands of DNA to store the data in a way that scientists can then read. Eventually, it could turn cells into environmental sensors, enabling them to report on their exposure to particular chemicals, among other applications.“They’ve done a really exceptional job turning DNA into readable, writable memory inside living cells,” says Ahmad Khalil, a biomedical engineer at Boston University who was not involved in the new work. “I think it’s a very cool new direction for synthetic biology to take.”In the past, researchers have turned cells into simple sensors by switching on or off the production of proteins in response to a stimulus. But each switch could record only one simple piece of information—whether the cell had been exposed to the stimulus—not the duration or magnitude of this exposure. And if the cell died, the information—encoded in a protein—would be lost.Sign up for our daily newsletterGet more great content like this delivered right to you!Country *AfghanistanAland IslandsAlbaniaAlgeriaAndorraAngolaAnguillaAntarcticaAntigua and BarbudaArgentinaArmeniaArubaAustraliaAustriaAzerbaijanBahamasBahrainBangladeshBarbadosBelarusBelgiumBelizeBeninBermudaBhutanBolivia, Plurinational State ofBonaire, Sint Eustatius and SabaBosnia and HerzegovinaBotswanaBouvet IslandBrazilBritish Indian Ocean TerritoryBrunei DarussalamBulgariaBurkina FasoBurundiCambodiaCameroonCanadaCape VerdeCayman IslandsCentral African RepublicChadChileChinaChristmas IslandCocos (Keeling) IslandsColombiaComorosCongoCongo, The Democratic Republic of theCook IslandsCosta RicaCote D’IvoireCroatiaCubaCuraçaoCyprusCzech RepublicDenmarkDjiboutiDominicaDominican RepublicEcuadorEgyptEl SalvadorEquatorial GuineaEritreaEstoniaEthiopiaFalkland Islands (Malvinas)Faroe IslandsFijiFinlandFranceFrench GuianaFrench PolynesiaFrench Southern TerritoriesGabonGambiaGeorgiaGermanyGhanaGibraltarGreeceGreenlandGrenadaGuadeloupeGuatemalaGuernseyGuineaGuinea-BissauGuyanaHaitiHeard Island and Mcdonald IslandsHoly See (Vatican City State)HondurasHong KongHungaryIcelandIndiaIndonesiaIran, Islamic Republic ofIraqIrelandIsle of ManIsraelItalyJamaicaJapanJerseyJordanKazakhstanKenyaKiribatiKorea, Democratic People’s Republic ofKorea, Republic ofKuwaitKyrgyzstanLao People’s Democratic RepublicLatviaLebanonLesothoLiberiaLibyan Arab JamahiriyaLiechtensteinLithuaniaLuxembourgMacaoMacedonia, The Former Yugoslav Republic ofMadagascarMalawiMalaysiaMaldivesMaliMaltaMartiniqueMauritaniaMauritiusMayotteMexicoMoldova, Republic ofMonacoMongoliaMontenegroMontserratMoroccoMozambiqueMyanmarNamibiaNauruNepalNetherlandsNew CaledoniaNew ZealandNicaraguaNigerNigeriaNiueNorfolk IslandNorwayOmanPakistanPalestinianPanamaPapua New GuineaParaguayPeruPhilippinesPitcairnPolandPortugalQatarReunionRomaniaRussian FederationRWANDASaint Barthélemy Saint Helena, Ascension and Tristan da CunhaSaint Kitts and NevisSaint LuciaSaint Martin (French part)Saint Pierre and MiquelonSaint Vincent and the GrenadinesSamoaSan MarinoSao Tome and PrincipeSaudi ArabiaSenegalSerbiaSeychellesSierra LeoneSingaporeSint Maarten (Dutch part)SlovakiaSloveniaSolomon IslandsSomaliaSouth AfricaSouth Georgia and the South Sandwich IslandsSouth SudanSpainSri LankaSudanSurinameSvalbard and Jan MayenSwazilandSwedenSwitzerlandSyrian Arab RepublicTaiwanTajikistanTanzania, United Republic ofThailandTimor-LesteTogoTokelauTongaTrinidad and TobagoTunisiaTurkeyTurkmenistanTurks and Caicos IslandsTuvaluUgandaUkraineUnited Arab EmiratesUnited KingdomUnited StatesUruguayUzbekistanVanuatuVenezuela, Bolivarian Republic ofVietnamVirgin Islands, BritishWallis and FutunaWestern SaharaYemenZambiaZimbabweI also wish to receive emails from AAAS/Science and Science advertisers, including information on products, services and special offers which may include but are not limited to news, careers information & upcoming events.Required fields are included by an asterisk(*)“We wanted a system that would be easier to scale up to collect more than one piece of information,” says synthetic biologist Timothy Lu of the Massachusetts Institute of Technology in Cambridge. “So we started out, as engineers, thinking about what an ideal memory system would look like.”Lu’s team settled on a biological program that rewrites a living cell’s DNA when the cell senses a signal—from a flash of light to the presence of a chemical. Once the DNA is altered, the information remains embedded in the genetic material even if the cell dies. By sequencing the genes of a population of cells that all contain the program, researchers can determine the magnitude and duration of the signal: The more cells have the genetic mutation, the stronger or longer the signal was.The approach, dubbed Synthetic Cellular Recorders Integrating Biological Events (SCRIBE), relies on retrons—which make up a genetic system found naturally in some bacteria that produces single-stranded DNA that the bacteria normally use to alter their host. Lu’s team started with bacterial cells and inserted a retron that would be turned on—producing the unique DNA—only in response to a specific stimulus like a chemical. While the cell is in the process of copying its genetic material, the new DNA would then replace a nearly identical existing gene segment in the cell, changing it slightly.  Lu tested SCRIBE on cells that he engineered to sense light, as well as others that responded to a common biological reagent. In one instance, he made the memory especially easy to read by engineering the cells to mutate an antibiotic resistance gene in response to light. When cells were then grown in the presence of the antibiotic, the researchers could immediately see which cells contained the new gene. The results were confirmed by sequencing the bacteria’s genomes. But SCRIBE, described online today in Science, could be designed to sense other stimuli and cause any desired genetic mutation in return.“There are a bunch of potential applications of this system,” Lu says. “One is being able to do long-term recording of a cell’s environment.” For example, he says, living cells could be left in an area of water for a week, then collected. Sequencing the DNA from the cells could then reveal whether the cells had been exposed to certain bacteria or toxins in the water. SCRIBE could also be a boon to basic researchers, Lu adds. “During development, as you go from a single cell to a multicellular organism, each cell encounters different cues,” he says. SCRIBE could let researchers record what each cell encountered to shape its fate.“What’s neat about this strategy is that you have a lot more diversity and flexibility than other methods to give cells memory,” Khalil says. Because scientists can choose the stimulus—or multiple different stimuli—that they want the cell to record, as well as what gene change they want to use as a marker, the possibilities for applications are wide, he says.last_img read more

South Florida kids celebrate reading with Dr Seuss books

first_imgMIAMI (WSVN) – South Florida children on Thursday celebrated Dr. Seuss’ birthday by reading his books.It was part of the National Education Association’s Read Across America Day. The NEA celebrated their own anniversary by having kids in every community read a Doctor Seuss book.United Way Women’s Leadership members took part in the event by reading to kids at the United Way Center in Miami.Copyright 2019 Sunbeam Television Corp. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.last_img

Costa Rica hosts its first Songwriters Festival

first_imgCosta Rica is holding its first-ever International Songwriters Festival this week at the Melico Salazar Theater in downtown San José,  allowing the public to watch participants from nine countries present their original compositions and compete for a $5,000 prize.The festival, which kicked off last night with an opening ceremony featuring Peruvian singer-songwriter Julie Freundt and Costa Rican songwriter Humberto Vargas, will conclude on July 7, when the winner will be announced and a concert will be offered by Carlos Mejía Godoy and the Palacaguinas (Nicaragua) and Adrián Goizueta (Argentina).Susana Poveda, executive directorof the Festival, told The Tico Times that Costa Rica’s entry in the competition was chosen during ast year’s Transitarte festival.“Immediately afterwards, the international call for participants took place,” Poveda said. “We received many proposals from many different countries. Winners were selected from 1500 participants.”The contest will feature ten participants from nine different countries, who will be defending their original creations. The participants are Rosalía León (Mexico), Wahari Meléndez (Venezuela), Covi Quintana (Dominican Republic), Solo Valencia (Colombia), Jesús Gárriga (Spain), Oscar Sandoval (El Salvador), Tamela Hedstron (Sweden), Oscar Pino (Costa Rica), Mariana Poblete (Argentina), and Rodrigo Carazo (Argentina).The jury is composed of Goizueta; Julie Freundt and Javier Malca from Peru; Chico Luis Mejía from Nicaragua; Adrián Goizueta; Miguel Inzunza from Mexico; and two Costa Ricans, the poet Osvaldo Sauma and Grammy award-winner Walter Flores.Several activities will be taking place through July 10:July 7Finale of the contest, announcement of the winner and a concert by Carlos Mejía Godoy and the Palacaguina, and Adrián Goizueta.Melico Salazar Theater, downtown San José. 8 p.m. ₡5,000 – 15,000 ($10 – 30). Tickets on sale at Eticket.com or at the theater ticket office. July 8Contest participants and Dionisio Cabal sing for peace. Teatro 1887, Cenac, downtown San José. 10 a.m. Free. Songwriting workshop with Miguel Inzunza and Rosalía León from Mexico, and Natalia Esquivel and Yessenia Calvo from Costa Rica. At Mexican Institute, Los Yoses. 3 p.m. Free. Concert with Jesús Garriga, Covi Quintana, Oscar Sandoval, and Solo Valencia. At Spain Cultural Center El Farolito, San José. 7 p.m. Free. Concert with Christian Porras, Alejo García, Wahari Melendez, Rodrigo Carazo, and Mariana Poblete. At El Sótano, San José. 9 p.m.Concert with Julie Freudt and Oscar Pino. At Jazz Café Escazú. 9 p.m.July 9Concert with Miguel Inzunza and Bernardo Quesada. At Jazz Café San Pedro. 9 p.m.July 10Concert with all contest participants. At Multiplaza Escazú, in front of Brunos Restaurant. 4 p.m. Free. Find more info at the International Songwriters Festival of Costa Rica website. Facebook Comments Related posts:Arts and culture in brief: the week ahead in Costa Rica ‘Abominable Creatures,’ contemporary dance, and other happenings around Costa Rica Dance Company performance, La Llorona, and other happenings around Costa Rica Delicious eats for your holiday celebrationslast_img read more