01161nas a2200157 4500008004100000022001400041245012300055210006900178260011000247300001400357490000600371520044600377100002400823700002600847856013000873 2010 eng d a1477-052000aAmino/guanidino-functionalized N-(pyrrolidin-2-ethyl)glycine-based pet-PNA: design, synthesis and binding with DNA/RNA0 aAminoguanidinofunctionalized Npyrrolidin2ethylglycinebased petPN aTHOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLANDbROYAL SOC CHEMISTRYcJUN a3742-37500 v83 a

The N-(pyrrolidin-2-ethyl) glycine-based PNA (pet-PNA) backbone, with 4-amino or 4-guanidino-functionalized pyrrolidine ring, confers constrained conformational flexibility on aegPNA. The oligomers bind to the target DNA and RNA sequences with increased sequence specificity and antiparallel versus parallel orientation selectivity. The easy post-synthetic guanidination gives very good access to the positively charged PNA oligomers.

1 aGokhale, Sachin, S.1 aKumar, Vaijayanti, A. uhttps://library.ncl.res.in/content/aminoguanidino-functionalized-n-pyrrolidin-2-ethylglycine-based-pet-pna-design-synthesis-001528nas a2200169 4500008004100000022001400041245019800055210006900253260007100322300001400393490000700407520074700414100002401161700001801185700002601203856012901229 2010 eng d a0022-326300aProbing binding preferences of DNA and RNA: backbone chirality of thioacetamido-linked nucleic acids and iso-thioacetamido-linked nucleic acids to differentiate DNA versus RNA selective binding0 aProbing binding preferences of DNA and RNA backbone chirality of a1155 16TH ST, NW, WASHINGTON, DC 20036 USAbAMER CHEMICAL SOCcNOV a7431-74340 v753 a

Subtle differences in RNA and DNA duplex geometry could be sensed by the changed stereochemistry at 3 `-amino function in the 5-atom thioacetamido linker of thioacetamido-linked nucleic acids and iso-thioacetamido-linked nucleic acids modified oligomers. In contrast to the preferred N-type sugar conformations for either 3 `- ribo- or xylo amino nucleosides, predominant S-type sugar conformations were found in the dimers. Although the CD spectral differences for the dimer blocks were found to be identical for those found in phosphodiester linked ribo/xylo dimers, the 5-atom thioactamido linker could reverse the RNA binding selectivity to DNA binding selectivity by the change in configuration at the 3 `-amino-substituted sugar.

1 aGokhale, Sachin, S.1 aGogoi, Khirud1 aKumar, Vaijayanti, A. uhttps://library.ncl.res.in/content/probing-binding-preferences-dna-and-rna-backbone-chirality-thioacetamido-linked-nucleic-002268nas a2200217 4500008004100000022001400041245007700055210006900132260008700201300001200288490000700300520149000307100001701797700001901814700002401833700001601857700002201873700002601895700001801921856011101939 2013 eng d a2159-333700aDetection and knockdown of MicroRNA-34a using thioacetamido nucleic acid0 aDetection and knockdown of MicroRNA34a using thioacetamido nucle a140 HUGUENOT STREET, 3RD FL, NEW ROCHELLE, NY 10801 USAbMARY ANN LIEBERT INCcJUN a195-2020 v233 a

Thioacetamido nucleic acids (TANA) contain a backbone modification of dinucleotides consisting of a 5-atom amide linker N3'-COCH2-S-CH2 at thymidine or thymidine-cytidine dimer blocks. Here, the chemical synthesis of the TANA linked 5-methyl-cytidine-cytidine ((Me)cc) dimer block and its incorporation into the DNA sequence, complementary to human microRNA 34 (miR-34) is described. Further, for the first time, we demonstrate the biological applications of TANA modified oligonucleotides in detection and intracellular knockdown of a cancer related microRNA in comparison with DNA containing locked nucleic acid (LNA) and 2'-O-methyl modifications. The human microRNA miR-34 is a pro-apoptotic microRNA under the transcriptional control of protein 53 (p53). It gets expressed in response to DNA damage and regulates several cell cycle and apoptosis related targets. Here, we show that the TANA modified antisense oligonucleotide binds specifically to miR-34a, allowing its detection using primer extension. We also show that, using the TANA modified antisense oligonucleotide against miR-34a, intracellular levels of miR-34 can be reduced, and consequently, the expression of its target oncogene V-myc myelocytomatosis viral related oncogene, neuroblastoma derived (MYCN) is enhanced. Further, we assessed the toxicity and serum stability of the oligonucleotide to conclude that it is suitable for detection and modulation of the vital biomarker and tumor suppressor microRNA.

1 aSoni, Kartik1 aGupta, Shivani1 aGokhale, Sachin, S.1 aDey, Rakesh1 aGunjal, Anita, D.1 aKumar, Vaijayanti, A.1 aPillai, Beena uhttps://library.ncl.res.in/content/detection-and-knockdown-microrna-34a-using-thioacetamido-nucleic-acid-0