NEWS OF THE W EEK
Protein
Release bar codes using UV light
Detect
DNA bar codes
ADAPTED FROM SCI. TRANSL. MED.
Antibody
SPOTTING PROTEINS ON SINGLE CELLS
teins on the same cell, write Yesim Gökmen-Polar and Sunil Badve of Indiana University School of Medicine, Indianapolis, in a commentary about the work. In the technique, target proteins must be determined in advance and high-quality antibodies must be available or developed for them. The antibodies are linked to single-stranded DNA “bar codes” via a photocleavable linker developed earlier by Weissleder’s group. When mixed with lysed cells, the antibodies bind to specific proteins. Ultraviolet light releases the DNA bar codes from the antibody-protein complexes. The DNA bar codes, and the proteins they represent, are then identified through their sequence-specific binding to complementary DNA strands tagged with fluorescent groups. The technique achieved simultaneous analysis of hundreds of protein markers from patients’ cells. “Instead of trying to procure more tissue to study, we shrank the analysis process so that it could now be performed on a few cells,” says team member Cesar M. Castro, an MGH oncologist. Those cells are obtained with minimal invasiveness, such as by using fine needles to aspirate sample fluids from patients. The study revealed divergences in protein expression among different tumor samples. It also identified proteins that distinguish cancer patients who respond well to drug treatment from those who don’t. The method “could be very important for early detection of disease and for monitoring the effectiveness of treatments,” comments Piotr Grodzinski, director of cancer nanotechnology programs at the National Cancer Institute.—STU BORMAN
COURTESY OF THE OFFICE OF BARBARA MIKULS KI
Technique uses antibody/DNA-barcode conjugates to target specific cell-surface proteins. UVinduced bar code release, followed by hybridization with complementary DNA, enables the DNA bar codes, and the proteins they represent, to be identified fluorescently.
propriations Committee Chair Barbara A. Mikulski (DMd.) hammered out the nearly 1,600-page bipartisan agreement over the past few weeks. The $1.012 trillion omnibus appropriations bill (H.R. 3547) boosts funding for nearly all science agencies as compared with fiscal 2013 sequester levels, according to congressional summaries. NSF would be funded at $7.172 billion for 2014, up $288 million from 2013 sequester levels; NIH would get $29.926 billion, up about $1 billion; and the Department of Energy would get $26.466 billion, up $1.317 billion. Mikulski noted when unveiling the measure on Jan. 13 that the agreement encompasses all federal appropriations, which Congress historically addresses in 12 separate bills. She added that this omnibus bill represents the first time since 2011 that lawmakers have provided guidance across all federal programs. One of the bill’s provisions would require all federal agencies or bureaus with R&D expenditures above $100 million to set up an open-access policy and to make final peer-reviewed manuscripts resulting from federally funded work freely available online no later than 12 months after publication. Absent from this bill are directives on many contentious policy issues such as carbon dioxide regulations by EPA.—SUSAN MORRISSEY
ANALYTICAL BIOCHEMISTRY: DNAbased sensing of multiple proteins could aid personalized medicine
U
SING ANTIBODIES and little pieces of DNA,
a new technique detects hundreds of different proteins on individual cells. It could be used to study protein variations—on different cells in the same tumor, for example—analyze reDNA bar code sponses to drugs, and diagnose diseases. Ralph Weissleder of MassachuPhotocleavable linker setts General Hospital (MGH) and coworkers developed the technique and demonstrated its ability to identify proteins on cells from patients with lung or skin cancer (Sci. Transl. Med. 2014, DOI: 10.1126/ scitranslmed.3007361). Weissleder notes that mass spectrometry “can do something similar, but it is not commonly used” in clinical applications because it is expensive. Fluorescent The work is “a major step forgroup ward” in scientists’ efforts to detect simultaneously many different pro-
CONGRESS SETS 2014 BUDGET APPROPRIATIONS: Funding increases for R&D agencies under bipartisan deal Mikulski and Rogers are the architects of the bipartisan appropriations measure set to become law.
T
HE HOUSE OF REPRESENTATIVES passed a
massive budget measure last week that would set federal funding levels and provide guidance for fiscal 2014 to all agencies and programs—including those related to R&D. The Senate was expected to pass the measure after C&EN’s press deadline. The action comes nearly four months into the fiscal year, which started on Oct. 1, 2013. “This legislation is one of our highest priorities as members of Congress, and it is critical to our ongoing economic stability and the safety of the American people,” said House Appropriations Committee Chair Hal D. Rogers (R-Ky.). Rogers and Senate ApC E N. ACS.ORG
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