Researchers use DNA to take pictures of cells

first_img Sign up for our daily newsletter Get more great content like this delivered right to you! Country To look at a cell, you used to need a microscope. Now, researchers have found a way to view cells by using their own genetic material to take snapshots. The technique—called DNA microscopy—produces images that are less clear than those from traditional microscopy, but that could enable scientists to improve cancer treatment and probe how our nervous system forms.“DNA microscopy is an ingenious approach,” says geneticist Howard Chang of the Stanford University School of Medicine in Palo Alto, California, who wasn’t connected to the research. “I think it will be used.”To make the DNA microscope, postdoc Joshua Weinstein of the Broad Institute of in Cambridge, Massachusetts, and colleagues started with a group of cells in a culture dish. By creating DNA versions of the RNA molecules in the cells, they produced a large number of DNA molecules they could track. They then added tags—short pieces of DNA—that latched onto these DNA duplicates. Next, the scientists mixed in chemicals that produce multiple copies of these tags and the DNA molecules they connect to. As these copies built up, they started to drift away from their original location. When two wandering DNA molecules ran into each other, they linked up and spawned a unique DNA label that marked the encounter. Researchers use DNA to take pictures of cells Weinstein et al./Cell A group of cells captured with a traditional optical microscope (left) and with DNA microscopy (right) By Mitch LeslieJun. 20, 2019 , 11:00 AMcenter_img Country * Afghanistan Aland Islands Albania Algeria Andorra Angola Anguilla Antarctica Antigua and Barbuda Argentina Armenia Aruba Australia Austria Azerbaijan Bahamas Bahrain Bangladesh Barbados Belarus Belgium Belize Benin Bermuda Bhutan Bolivia, Plurinational State of Bonaire, Sint Eustatius and Saba Bosnia and Herzegovina Botswana Bouvet Island Brazil British Indian Ocean Territory Brunei Darussalam Bulgaria Burkina Faso Burundi Cambodia Cameroon Canada Cape Verde Cayman Islands Central African Republic Chad Chile China Christmas Island Cocos (Keeling) Islands Colombia Comoros Congo Congo, the Democratic Republic of the Cook Islands Costa Rica Cote d’Ivoire Croatia Cuba Curaçao Cyprus Czech Republic Denmark Djibouti Dominica Dominican Republic Ecuador Egypt El Salvador Equatorial Guinea Eritrea Estonia Ethiopia Falkland Islands (Malvinas) Faroe Islands Fiji Finland France French Guiana French Polynesia French Southern Territories Gabon Gambia Georgia Germany Ghana Gibraltar Greece Greenland Grenada Guadeloupe Guatemala Guernsey Guinea Guinea-Bissau Guyana Haiti Heard Island and McDonald Islands Holy See (Vatican City State) Honduras Hungary Iceland India Indonesia Iran, Islamic Republic of Iraq Ireland Isle of Man Israel Italy Jamaica Japan Jersey Jordan Kazakhstan Kenya Kiribati Korea, Democratic People’s Republic of Korea, Republic of Kuwait Kyrgyzstan Lao People’s Democratic Republic Latvia Lebanon Lesotho Liberia Libyan Arab Jamahiriya Liechtenstein Lithuania Luxembourg Macao Macedonia, the former Yugoslav Republic of Madagascar Malawi Malaysia Maldives Mali Malta Martinique Mauritania Mauritius Mayotte Mexico Moldova, Republic of Monaco Mongolia Montenegro Montserrat Morocco Mozambique Myanmar Namibia Nauru Nepal Netherlands New Caledonia New Zealand Nicaragua Niger Nigeria Niue Norfolk Island Norway Oman Pakistan Palestine Panama Papua New Guinea Paraguay Peru Philippines Pitcairn Poland Portugal Qatar Reunion Romania Russian Federation Rwanda Saint Barthélemy Saint Helena, Ascension and Tristan da Cunha Saint Kitts and Nevis Saint Lucia Saint Martin (French part) Saint Pierre and Miquelon Saint Vincent and the Grenadines Samoa San Marino Sao Tome and Principe Saudi Arabia Senegal Serbia Seychelles Sierra Leone Singapore Sint Maarten (Dutch part) Slovakia Slovenia Solomon Islands Somalia South Africa South Georgia and the South Sandwich Islands South Sudan Spain Sri Lanka Sudan Suriname Svalbard and Jan Mayen Swaziland Sweden Switzerland Syrian Arab Republic Taiwan Tajikistan Tanzania, United Republic of Thailand Timor-Leste Togo Tokelau Tonga Trinidad and Tobago Tunisia Turkey Turkmenistan Turks and Caicos Islands Tuvalu Uganda Ukraine United Arab Emirates United Kingdom United States Uruguay Uzbekistan Vanuatu Venezuela, Bolivarian Republic of Vietnam Virgin Islands, British Wallis and Futuna Western Sahara Yemen Zambia Zimbabwe Email Click to view the privacy policy. Required fields are indicated by an asterisk (*) These labels are crucial for capturing a DNA image of the cells. If two DNA molecules start out close to each other, their diffusing copies will hook up frequently and produce more labels than two DNA molecules that start out farther apart. To count the labels, the researchers grind up the cells and analyze the DNA they contain. A computer algorithm can then infer the original positions of the DNA molecules to generate an image.In a sense, Weinstein says, the original DNA molecules are like radio towers that send messages in the form of DNA molecules to each other. Researchers can detect when one tower communicates with another one nearby and use the pattern of transmissions among towers to map their locations.To determine how well the technique works, the researchers tested it on cells carrying genes for either green or red proteins. The image created with DNA microscopy was not as sharp as one the researchers obtained with a light microscope, but it distinguished the genetically distinct red and green cells, the team reports today in Cell. In addition, Weinstein says, it captured the arrangement of the cells. That ability could be useful in analyzing a sample from, say, an organ in a human body. The technique can’t yet reveal fine details within cells, however.“The goal is not to replace optical microscopy,” Weinstein says. But DNA microscopy can do some things optical microscopy can’t. For instance, optical microscopy often can’t distinguish among cells with DNA differences, such as tumor cells with specific mutations or immune cells, which are often genetically unique after shuffling their DNA. Weinstein says DNA microscopy may help improve certain cancer treatments by identifying immune cells that can attack tumors. As our nervous system develops, cells often produce unique RNAs that enable them to make specialized proteins, and the technique could also help researchers investigate these cells.The technique is “pretty cool,” says molecular technologist Joakim Lundeberg of the KTH Royal Institute of Technology in Stockholm, who helped develop an approach for visualizing RNA in cells. But he cautions that the study is preliminary and that researchers still need to determine the technique’s capabilities. DNA microscopy would be valuable if it could produce 3D images of cells in a sample, he says. “They need to demonstrate this in a tissue to really understand how useful it is.”last_img read more

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