WilsonLab @WilsonLab2
Ribosomes & Translation Regulation; Antibiotics & Resistance Mechanisms; Structural Biology & Cryo-EM; University of Hamburg. chemie.uni-hamburg.de/bc/wilson Hamburg, Germany Joined June 2018-
Tweets3K
-
Followers2K
-
Following485
-
Likes7K
New online! Integrated structural biology of the native malarial translation machinery and its inhibition by an antimalarial drug bit.ly/4mluP07
Our #CryoET story on how a top antimalarial drug candidate perturbs the native malarial translation machinery is out @NatureSMB🥳rdcu.be/eBbrH Massive team effort led by @leonie_anton @mehsehret @Wenjing_Cheng_ in collaboration with @DziekanJerzy @CowmanAlan #teamtomo
Out Now! Deep learning reveals antibiotics in the archaeal proteome bit.ly/4lpohMM #DeepLearning #ArtificialIntelligence #Antibiotics
Our RAPPL purification of ribosomes and associated material is finally out. I am really proud of this study in collaboration primary with @slavicaPD lab, as well as Marko Jovanovic and @Hashemyaser4 Labs. This method aims to replace 60 years old purification of ribosomes by…
Check out our new preprint on the discovery of a molecular switch in NAC that mediates nascent chain sorting on the ribosome and prevents mitochondrial protein mistargeting by SRP. A great collaboration with the Shan Lab @Caltech and the Qi Lab @UVA: biorxiv.org/content/10.110…
We are excited to share our latest research on Q-modification in precursor-tRNAs, which just got published in @NatureComms. This was an very exciting and fruitful collaboration with @francescatuorto in Heidelberg. nature.com/articles/s4146…
How many plasmids can bacteria carry? A synthetic biology perspective doi.org/10.1098/rsob.2…
Out Now! Structure of an archaeal ribosome reveals a divergent active site and hibernation factor bit.ly/3UhiSfp #Archaea #RibosomeStructure #PeptidylTransferase
Preprint from our collaboration with the labs of Gerry Wright and Shura Mankin @shuramankin identifying the first translation inhibitor binding to the E-site of the bacterial ribosome… researchsquare.com/article/rs-692…
New paper out in Mol Cell, where we show how N-myristolytransferases lipidate proteins on the translating ribosome! Continuing our successful collaboration with @DeuerlingLab & Shu-ou Shan @Caltech @snsf_ch @ETH_en cell.com/molecular-cell…
Thrilled that Patrick Cramer @mpgpresident was elected a Foreign Member @royalsociety, here at today's event! 🥳Congratulations also to Max Planck appointees Miltos Tsiantis @mpipz_cologne , elected as Fellow, Detlef Lohse & Claudia Felser @mpi_CPfS - science is international!😊
Mammalian tRNA acetylation determines translation efficiency and tRNA quality control doi.org/10.1038/s41467…
@DjuranovicLab is from today officially part of @BrownUniversity and Brown RNA center. We will have our new website soon. rna.brown.edu
Time-resolved cryo-electron microscopy can resolve protein motion on millisecond or even microsecond timescales, but the need for highly specialized tools and skills limits the method’s reach nature.com/articles/d4158…
With our RTI colleagues Xiaobin Ling and @WenwenFang2, we report cryo-EM structures of enigmatic bacterial RNA nanocages made of long-noncoding ROOL RNAs. Octamers are held by "A-minor staples" and other interactions. Congrats Xiaobin, Dima et al! nature.com/articles/s4158…
Activation of Retron-Septu for antiphage defense. Congrats @futianmin and all co-authors! science.org/doi/full/10.11…
Doudna super computer :)
Designing New Chimeric Proline-Rich Antimicrobial Peptides to Enhance Efficacy Toward the ESKAPE+E: Beyond Sequence Extension mdpi.com/2218-273X/15/6…
Congratulations! The #ShawPrize in Life Science & Medicine 2025 is awarded to Wolfgang Baumeister for his pioneering development & use of cryo-ET. ❕shawprize.org/laureates/2025… @ShawPrize #CryoEM #cryoET #Award

Israel Fernandez @IsraelF96135088
4K Followers 1K Following Action is the offspring of dark pessimism.
Jeffrey Kieft @JeffreyKieft
3K Followers 644 Following Executive Director, NYSBC (@NYSBC_Science); RNA biochemist, biophysicist, structural biologist, and virologist. Go Army, Beat Navy! pronouns: he/him/his
Chris H. Hill @chillzaa
2K Followers 1K Following Wellcome Fellow, PI, Lecturer 🔬🧬🏳️🌈 @BiologyatYork @YBRI_UoY @YSBL_York He/him. Viral gene expression, ribosomes, RNA, cryoEM, X-ray crystallography. 🎹🎶
Jay Brito Querido @Jayquerido
895 Followers 741 Following Assistant Professor at the @UMichMedSchool and Research Assistant Professor at the @UMLifeSciences
Sergej Djuranovic @DjuranovicLab
1K Followers 300 Following Biochemistry, Genetics and RNA biology lab at Brown University RNA Center.
Misha Kudryashev 🔬... @MishaKudryashev
5K Followers 854 Following Group Leader at the Max Delbruck Center for Molecular Medicine @MDC_Berlin Professor at Charité in Berlin Immigrant Science / Biophysics / Cryo-EM
Kelly Nguyen @KellyTHD_Nguyen
6K Followers 1K Following Group Leader @MRC_LMB /Structural Biologist/Biochemist. Amateur baker in free time #RNAworld #spliceosome #telomerase #telomeres #cryoEM #Xraycrystallography
Neva Caliskan @nevacaliskan
1K Followers 343 Following Chair of Biochemistry III in University of Regensburg. Group leader at #Helmholtz_HIRI 👩🔬 main focus on #RNA, alternative translation events and viruses.
Andreas Boland @BolandLab_GE
4K Followers 3K Following Professor at University of Geneva. https://t.co/RfDg6e8gDU Biochemistry and Structural Biology @UNIGEnews; views are my own 🇩🇪 🇨🇭 🇬🇧 RT ≠ endorsement
Davide Ruggero @RuggeroDavide
2K Followers 632 Following
Structura Biotechnolo... @structurabio
6K Followers 410 Following Algorithms, Software and Systems for Cryo-EM. Makers of CryoSPARC.
Zeynep Baharoglu @BaharogluZeynep
1K Followers 1K Following Scientist - Group leader at Institut Pasteur Paris - Bacterial stress responses, sub-MIC antibiotics, AMR, RNA modifications
Sebastian Glatt @GlattSebastian
1K Followers 908 Following Max Planck Research Group Leader tRNAslational Control of eukaryotic Gene Expression Structural Biology #tRNA #Elongator #Urm1 #RNA
Akos T. Kovacs @EvolvedBiofilm
21K Followers 2K Following Professor of Microbiome Ecology at @LeidenBiology 🇳🇱, posting mostly at 🦋: @evolvedbiofilm.bsky.social; also @MicroClockERC #ERCSyG
Ariane Briegel @BriegelAriane
4K Followers 956 Following Professor, Leader of the Integrative Structural Cell Biology Unit at Institut Pasteur @[email protected]
Jörg Stülke @JorgStulke
2K Followers 257 Following #bacillus #subtiwiki #MiniBacillus @Bacell_EU @Rafts4Biotech @SPP1879 @UniGoettingen
SPC Facility & Garcia... @SPC_EMBL_HH
633 Followers 679 Following Sample Preparation and Characterisation Facility at EMBL-Hamburg. Molecular Biophysics & integrative structural biology.
hopfnerlab @hopfnerlab
1K Followers 225 Following Structural biology on DNA repair, chromatin remodeling and innate immunity.
Dunham Lab @DunhamLabEmory
568 Followers 269 Following Love RNA? Sometimes we do too! Official twitter account of the Dunham Lab @emoryuniversity, of Dr. Christine Dunham (@Dunham_Lab)!
MrChizim @Major_felixx
948 Followers 2K Following MSc Biochemistry: Uppsala University | BSc Biochemistry: University of port harcourt | Gym and Anime lover lol.
Kervens Accilien @AccilienKervens
37 Followers 117 Following 🇭🇹 ⛪️ 👨🏾🔬 PhD candidate at University of Kansas. Unckless lab. #biochem #evolution #AntimicrobialPeptides #AMR
macy ma @machy456
0 Followers 41 Following
Sase @Sase297705
0 Followers 29 Following
Shabab Hannan, Dr. re... @hannan_shabab
143 Followers 282 Following 'Gotta roll up your sleeves to understand the brain', BCM Duncan NRI studying Alzheimer's in Houston now, German (Tuebingen), Rare diseases, views are my own
Thomas Veith @thomasaveith
799 Followers 3K Following Cancer biologist and computational modeler interested in tumor evolution, copy number alterations, and ecological dynamics in cancer.
Tokee Tareq @tokeemtareq
280 Followers 2K Following Lab Tech, interested in computational biology research.
Camila @Oliviac_Camila
8 Followers 451 Following When a woman becomes her own best friend, life is easier.
SeaCloudSac @SacCloud
88 Followers 2K Following
Shahid Ullah @Bch51Shahid
197 Followers 1K Following I am actively seeking a postdoctoral position with a research focus on hematology, leukemia/cancer genetics, and molecular biology
KennethJk98 @drunkass_jk
136 Followers 1K Following Y̶o̶u̶n̶g̶ ̶d̶u̶m̶b̶ (1998-2018) D̶r̶e̶a̶m̶ ̶H̶a̶r̶d̶ (2018-2021) Work Hard (2021-present) Master's student Neuro-disease in Drosophila
Samar Mohapatra @SamarMohap58498
0 Followers 16 Following
Loewui @Loewui48814
12 Followers 912 Following
Acta Pharmaceutica Si... @ActaPharmSinB
2K Followers 2K Following The Journal of the Chinese Pharmaceutical Association and the Institute of Materia Medica. #ImpactFactor= 14.6 #JCR=Q1(11/752). Published by @ElsevierConnect.
Mansi Srivastava @MansiSri9915
8 Followers 106 Following
Camila Brown @brow79424
15 Followers 52 Following I’m Camila brown I’m new and ready to meet up with new friends send a message and let’s chat
Aparichit @Aparichit8
26 Followers 403 Following ONE HAS TO PAY WHAT'ER CRIME HE MAKE IN THIS LIFE! -!! GARUDMAHAPURAN !!
Igor Kaczmarczyk @igorkaczm
267 Followers 495 Following PhD student @JagiellonskiUni, @GlattSebastian Lab, investigating biogenesis of tRNA modifications. Previously @weizmannscience, @ShalevBenamiLab
Arthur lightell @ArthurLigh7254
885 Followers 7K Following
Jaime Keller @ElizabethK58211
392 Followers 7K Following I work as an administrative assistant manager in Resource management sector. And also an investor 🪙💰💱
Pehe @Pehe7224
108 Followers 3K Following
Vicky Stamatopoulou @VStam3
12 Followers 52 Following Assistant Professor: RNA metabolism, ncRNAs, riboswitches
Sharmin Aktar @Sharmin64686895
2 Followers 56 Following
Karim H. Kholeif @KarimHKH
3 Followers 142 Following Graduate Student - Molecular Biology of Cellular Systems @RandauLab Marburg🧬✂️👨🔬
Rizwan naseem @riswannaseem
4 Followers 157 Following Research Scholar at Centre for Stem Cell Research
Berhanu Yitayew, PhD @yitayew_berhanu
144 Followers 627 Following Research Focus: Genomic Surveillance of Infectious disease & AMR from 'One Health' perspective, metagenomics
Titui @Titui023970
20 Followers 1K Following
Louis R. Lapierre Lab... @LapierreLab
2K Followers 2K Following Learning about aging and longevity / Étudier le vieillissement et la longévité
Prince @prince_prp
4 Followers 65 Following Of all things uncertain..... death is certain but when you are in the pursuit of Eternity.....Life becomes more meaningful than before......
Montalcini @montalcinihq
61 Followers 997 Following
Niya_ladyboydubai🇦... @srirtn117452
32 Followers 117 Following massage contact for Wattapp 052 789 45 48
Sigoney Silva @SigoneySilva
147 Followers 7K Following
Oswuel Granado @GranadoOsw10574
32 Followers 3K Following
Noe moises Castro oba... @castro_noe52810
48 Followers 2K Following
José Angel Gómez fe... @fedrick_jo51056
0 Followers 857 Following
Pedro Tovar @PTovar86811
1 Followers 57 Following
Bill Hubbard @hubbar89833
21 Followers 338 Following
Leandro Calixto @calixto_le58699
36 Followers 2K Following
Jordyn Raye @JordynRaye5
218 Followers 6K Following I am Me and I love my family and friends and my fur babies (cats) and I also have a great love for experimenting with my camera and creating unique pictures
Jemma Betts @JemmaBetts
36 Followers 107 Following PhD student in the Hill Lab @The_MRC @DiMeN_DTP @BiologyatYork @YBRI_UoY @YSBL_York
Jack O'Sullivan @watchrocksgrow
3 Followers 49 Following
Israel Fernandez @IsraelF96135088
4K Followers 1K Following Action is the offspring of dark pessimism.
Sjors Scheres @SjorsScheres
15K Followers 1 Following This account is no longer in use. Follow our science on: https://t.co/mlxULCj9zl
cryoEM Papers @cryoEM_Papers
12K Followers 0 Following I'm a bot that surveys the cryoEM literature for you! Operated by @fredericpoitev1 & @CorneliusGati, adapted from PaperBots twitter app developed by @fxcoudert
Jeffrey Kieft @JeffreyKieft
3K Followers 644 Following Executive Director, NYSBC (@NYSBC_Science); RNA biochemist, biophysicist, structural biologist, and virologist. Go Army, Beat Navy! pronouns: he/him/his
Chris H. Hill @chillzaa
2K Followers 1K Following Wellcome Fellow, PI, Lecturer 🔬🧬🏳️🌈 @BiologyatYork @YBRI_UoY @YSBL_York He/him. Viral gene expression, ribosomes, RNA, cryoEM, X-ray crystallography. 🎹🎶
Patrick Cramer @mpgpresident
14K Followers 578 Following President of the Max Planck Society since 2023 – dedicated to advancing science for the benefit of society. | @maxplanckpress
Jay Brito Querido @Jayquerido
895 Followers 741 Following Assistant Professor at the @UMichMedSchool and Research Assistant Professor at the @UMLifeSciences
Sergej Djuranovic @DjuranovicLab
1K Followers 300 Following Biochemistry, Genetics and RNA biology lab at Brown University RNA Center.
Molecular Cell @MolecularCell
142K Followers 525 Following Molecular Cell is a Cell Press journal that aims to publish the best papers in molecular biology.
Misha Kudryashev 🔬... @MishaKudryashev
5K Followers 854 Following Group Leader at the Max Delbruck Center for Molecular Medicine @MDC_Berlin Professor at Charité in Berlin Immigrant Science / Biophysics / Cryo-EM
Kelly Nguyen @KellyTHD_Nguyen
6K Followers 1K Following Group Leader @MRC_LMB /Structural Biologist/Biochemist. Amateur baker in free time #RNAworld #spliceosome #telomerase #telomeres #cryoEM #Xraycrystallography
Ribosome Papers @ribosome_papers
3K Followers 1 Following New #Ribosome papers from #Pubmed, #bioRxiv, and #arXiv. Also blogged at: https://t.co/M6psKeTonp | maintained by @slavovLab and @slavov_n
Neva Caliskan @nevacaliskan
1K Followers 343 Following Chair of Biochemistry III in University of Regensburg. Group leader at #Helmholtz_HIRI 👩🔬 main focus on #RNA, alternative translation events and viruses.
Andreas Boland @BolandLab_GE
4K Followers 3K Following Professor at University of Geneva. https://t.co/RfDg6e8gDU Biochemistry and Structural Biology @UNIGEnews; views are my own 🇩🇪 🇨🇭 🇬🇧 RT ≠ endorsement
Davide Ruggero @RuggeroDavide
2K Followers 632 Following
Structura Biotechnolo... @structurabio
6K Followers 410 Following Algorithms, Software and Systems for Cryo-EM. Makers of CryoSPARC.
ChimeraX (bsky: chime... @UCSFChimeraX
7K Followers 15 Following UCSF ChimeraX - software for visualizing biomolecules
Zeynep Baharoglu @BaharogluZeynep
1K Followers 1K Following Scientist - Group leader at Institut Pasteur Paris - Bacterial stress responses, sub-MIC antibiotics, AMR, RNA modifications
Sebastian Glatt @GlattSebastian
1K Followers 908 Following Max Planck Research Group Leader tRNAslational Control of eukaryotic Gene Expression Structural Biology #tRNA #Elongator #Urm1 #RNA
Inada Lab @inada_lab
43 Followers 37 Following 東京大学医科学研究所 総合研究棟1階 RNA制御学分野 学生が運営しています Welcome to inada lab official X!!
König Lab @koenig_lab
2K Followers 544 Following RNA biology group @Uni_WUE & formerly @IMBMainz Run by lab members 🧬 #Splicing #RNAModifications #RBPs #iCLIP #miCLIP #RQC
Meytal Landau @LandauMeytal
467 Followers 68 Following Scientist; DESY; CSSB; UKE; Technion; EMBL; Antimicrobials can Amyloid!; Can live on wine, bread and cherries
biorxiv_biochem @biorxiv_biochem
403 Followers 0 Following
Typas Lab @TypasLab
4K Followers 847 Following Systems Microbiology @EMBL, combining high-throughput approaches & mechanism in bacteria, antibiotics, microbiome, infection, species diversity, cell envelope
Andrea Rentmeister @RentmeisterLab
2K Followers 841 Following Researcher in Chemical Biology, Professor at LMU Munich @LMU_Muenchen
Ilya Osterman @IlyaOsterman
203 Followers 96 Following Senior Research Associate, @SorekLab, @WeizmannScience, the phage-host arms-race
npj Antimicrobials an... @npjAMR
1K Followers 898 Following Open for Submissions! OA journal by @NaturePortfolio Research, reviews & comments for the community 🦠💊 Ed-in-Chief @JessicaMABlair. https://t.co/oxCU6Nd3Sf
HornungLab @hornung_lab
2K Followers 136 Following We are interested in understanding how our innate immune system discriminates self from non-self. Tweets by students of the Hornung lab. Opinions are our own.
David Balchin @balchin_david
794 Followers 642 Following Biochemist interested in protein biogenesis. Group leader @TheCrick.
FrancescaTuorto @francescatuorto
406 Followers 950 Following Lost in Translation..... Division of Biochemistry, Mannheim Institute for Innate Immunoscience MI3
Remo Rohs @RemoRohs
3K Followers 5K Following Professor and Founding Chair, Department of Quantitative and Computational Biology, University of Southern California
Prem Kaushal @prem_s_kaushal
702 Followers 1K Following | #CryoEM, #Ribosome & Ghalib Bhakt (devotee) | Himalay Putra | Assoc. Prof. @unescorcb l #EMBO-GIN fellow
Sanford Lab @SanfordRNAlab
2K Followers 1K Following The Center for RNA molecular biology Department of molecular, cellular and developmental biology
Esther Park @Esth3rPark
187 Followers 206 Following Ph. D. Candidate Program in Molecular Biophysics | Hopkins | @GreenLabJHMI | Korean American 🇰🇷🇺🇸
Suzuki Lab. @SuzukiRNALab
354 Followers 222 Following We are discovering the physiological roles of RNA modifications in fundamental biological processes. https://t.co/mo8VBTifdc
Max Gemmer @MaxGemmer
424 Followers 593 Following PhD student at Utrecht University. Interested in Cryo-ET, protein biogenesis, endoplasmic reticulum. #TeamTomo #CryoEM #SciArt
Deniz Ugurlar @denizugurlar
688 Followers 637 Following Cryo-EM at Thermo Fisher Scientific @thermosciEMSpec PhD from Utrecht University @UtrechtUni. Opinions are my own.
BIOspektrum @Spektrum_BIO
2K Followers 1K Following BIOspektrum - Das Magazin für Biowissenschaften * Neue Themen aus der Wissenschaft * Nachrichten aus der Scientific Community
S-Bahn Hamburg @SBahnHamburg
77K Followers 48 Following 🚇Aktuelle Verkehrsmeldungen und Informationen auf https://t.co/9Nvpsi9ADe. Kundentelefon: (040) 3918-4385 Inaktiver Account der S-Bahn Hamburg
Akinobu Matsumoto Lab @MatsumoLab
207 Followers 206 Following We study gene expressions and their regulatory systems, as well as their molecular and physiological functions | #ribosomes #RNA #translation #transcription
Milon @pmilonma
1K Followers 455 Following Using science and technology to wonder about the magic realism of mind and nature
NatureStructMolBiol @NatureSMB
11K Followers 342 Following Nature Structural & Molecular Biology publishes top-quality research providing insight into how molecular components work together in biological processes.
Gene Yeo’s Lab at U... @yeo_lab
5K Followers 364 Following Gene Yeo's Lab: RNA regulation, technologies, disease models and therapeutics
hamburg.de @hamburg_de
254K Followers 240 Following Das offizielle Stadtportal. Impressum: https://t.co/6xkxBBHsTp Foto: https://t.co/tzpi1bDstM
FEUERWEHR HAMBURG @FeuerwehrHH
84K Followers 274 Following MOIN❗ Dies ist der offizielle X-Account der Feuerwehr Hamburg. Kein 24/7 Monitoring. Im Notfall immer ☎️ 112 wählen! #EinsatzfuerHamburg
Polizei Hamburg @PolizeiHamburg
242K Followers 57 Following Wir posten Mo-Fr (außer an Feiertagen) von 8 bis 18 Uhr & zu Sondereinsätzen. Hier keine Anzeigen, Notrufe, Hinweise! Im Notfall 110 wählen! Impressum:
Theoretical & Computa... @CompBioPhys
4K Followers 236 Following news and views from the research groups of H. Grubmüller, B. de Groot and A. Godec @mpi_nat Göttingen, Germany, Imprint: https://t.co/LsGpAHa8MP
tagesschau @tagesschau
5.3M Followers 269 Following Schlagzeilen von https://t.co/e4ZbhtdUqY - 🐘 https://t.co/fjId0qMfhq
Mayer Laboratory @mayer_lab
306 Followers 75 Following We study genome transcription and RNA processing and how their dysregulation leads to disease.
kathaRiNA Höfer @HoeferLab
2K Followers 738 Following The Höfer lab studies the epitranscriptomic mechanisms of gene regulation based on NAD-capped RNAs in bacteria. Tweets by KH We also joined @hoeferlab.bsky.soc
CEMCOF @cemcof
113 Followers 64 Following Cryo-Electron Microscopy and Tomography Core Facility @CEITEC_Brno @MasarykUni
Kat Ciazynska @KatCiazynska
716 Followers 711 Following Interested in structural biology, cryo-EM, proteins of all shapes and sizes. Views my own. she/her
Panos Poulis (current... @panos_poulis
326 Followers 632 Following Joint @maxplanckpress @WeizmannScience fellow | mRNA recoding in cancer and RNA-based therapeutics | PhD @mpi_nat | @panos-poulis.bsky.social
Dimitris Typas @DimitrisTypas
489 Followers 349 Following Senior Editor @NatureSMB. Views and opinions are personal.
Matthieu Gagnon @gagnon_lab
121 Followers 114 Following Associate Professor, Microbiology & Immunology/Biochemistry & Molecular Biology, Structural studies of translation machinery, Ribosome, Antibiotics, Cryo-EM
Paul Copeland @PRCLab
65 Followers 103 Following Running a research lab at Rutgers RWJMS, pursuing the molecular biology of selenocysteine, production of selenoproteins and the role of RNA binding proteins.
EustermannLab @EustermannLab
151 Followers 17 Following Exploring the energy-driven organization of chromatin
Himanshu Sharma @shrma_h
345 Followers 927 Following Group leader@NOVA-FCT. Parasites, viruses and cryoEM.
Daniel Terry @Daniel_S_Terry
2 Followers 25 Following
Kozo Tomita Lab: RNA ... @RnaLaboratory
397 Followers 132 Following Department of Computational Biology and Medical Sciences, Graduate School of Frontier Sciences, The University of Tokyo Kashiwa, Chiba 277-0882, Japan
Morkos Henen @morkos_henen
281 Followers 2K Following Associate Professor - Research, University of Colorado, Denver. Ph.D., Molecular biology (NMR), Vienna University.
JP Lab @JPLab_
694 Followers 575 Following Chromosome Segregation @ Wellcome Centre for Cell Biology @WTcell, Univ of Edinburgh, UK @GeneCenter_LMU, Munich, Germany
Wim Hagen @WimJHH
4K Followers 551 Following Cryo-EM. Playing drums with the world-famous Janse Bagge Bend.
SchlundtLabNMR @lab_nmr
359 Followers 378 Following We are working on post-transcriptional regulation and seek to understand the role of RNA elements and cognate RNA-binding proteins for the fate of an mRNA.