Cảnh quan biểu hiện và sự đồng điều chỉnh của các gen lão hóa đặc hiệu theo mô và loại tế bào ở người

Peng Xu1,2,3, Minghui Wang3,1,2, Won-min Song3,1,2, Qian Wang3,1,2, Guo-Cheng Yuan2,4, Peter H. Sudmant5,6, Habil Zare7,8, Zhidong Tu3,1,2, Miranda E. Orr9,10,11, Bin Zhang3,1,2,12
1Icahn Institute for Data Science and Genomic Technology, Icahn School of Medicine at Mount Sinai, New York, USA
2Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, USA
3Mount Sinai Center for Transformative Disease Modeling, Icahn School of Medicine at Mount Sinai, New York, USA
4Institute for Precision Medicine, Icahn School of Medicine at Mount Sinai, New York, USA
5Department of Integrative Biology, University of California, Berkeley, Berkeley, USA
6Center for Computational Biology, University of California, Berkeley, Berkeley, USA
7Department of Cell Systems & Anatomy, The University of Texas Health Science Center, San Antonio, USA
8Glenn Biggs Institute for Alzheimer’s and Neurodegenerative Diseases, University of Texas Health Sciences Center, San Antonio, USA
9Section of Gerontology and Geriatric Medicine, Department of Internal Medicine, Wake Forest School of Medicine, Winston-Salem, USA
10Salisbury VA Medical Center, Salisbury, USA
11Sticht Center for Healthy Aging and Alzheimer’s Prevention, Wake Forest School of Medicine, Winston-Salem, USA
12Department of Department of Pharmacological Sciences, Icahn School of Medicine at Mount Sinai, New York, USA

Tóm tắt

Lão hóa tế bào là một phản ứng căng thẳng phức tạp ảnh hưởng đến chức năng tế bào và sức khỏe của cơ thể. Nhiều yếu tố phát triển và môi trường, chẳng hạn như tín hiệu nội tại của tế bào, bức xạ, căng thẳng oxy hóa, gen ung thư và sự tích tụ protein, kích hoạt các gen và con đường có thể dẫn đến lão hóa. Đã có những nỗ lực to lớn để xác định và đặc trưng hóa các gen lão hóa (SnGs) trong các hệ thống căng thẳng và bệnh tật. Tuy nhiên, sự phổ biến của các tế bào lão hóa trong các mô khỏe mạnh của con người và chữ ký biểu hiện SnG toàn cầu ở các loại tế bào khác nhau chưa được hiểu rõ. Nghiên cứu này đã thực hiện một phân tích mạng lưới gen tích hợp dữ liệu RNA-seq của tế bào đơn và môi trường tổng thể trong các mô người không bị bệnh để điều tra chữ ký đồng biểu hiện SnG và tính đặc hiệu của chúng theo loại tế bào. Thông qua phân tích mạng lưới phiên mã toàn diện của 50 mô người trong dự án Biểu hiện Genotype-Tissue Expression (GTEx), chúng tôi đã xác định các mô đun gen giàu SnG, đặc trưng hóa các mẫu đồng biểu hiện SnG và xây dựng các mạng lưới SnG tổng hợp trên các mô chính của cơ thể người. Các phương pháp mạng lưới của chúng tôi đã xác định 51 SnG được bảo tồn cao ở tất cả các mô người, bao gồm cả các điều hòa viên tập trung vào CDKN1A (p21) điều khiển tiến trình chu kỳ tế bào và kiểu hình tiết liên quan đến lão hóa (SASP). Các mô đun giàu SnG cho thấy tính đặc hiệu theo loại tế bào đáng kể, đặc biệt là ở sợi bào, tế bào nội mô và tế bào miễn dịch. Các phân tích thêm về dữ liệu RNA-seq của tế bào đơn và dữ liệu phiên mã không gian đã xác thực độc lập những chữ ký SnG đặc hiệu theo loại tế bào được dự đoán bởi phân tích mạng. Nghiên cứu này đã tiết lộ có hệ thống các tổ chức đồng điều chỉnh và tính đặc hiệu theo loại tế bào của SnGs trong các mô chính của con người, điều này có thể phục vụ như một bản thiết kế cho các nghiên cứu trong tương lai để lập bản đồ các tế bào lão hóa và các tương tác tế bào của chúng trong các mô người.

Từ khóa

#lão hóa tế bào #gen lão hóa #phân tích mạng lưới gen #RNA-seq #mô người #tính đặc hiệu theo loại tế bào

Tài liệu tham khảo

Gorgoulis V, Adams PD, Alimonti A, Bennett DC, Bischof O, Bishop C, et al. Cellular senescence: defining a path forward. Cell. 2019;179(4):813–27. https://doi.org/10.1016/j.cell.2019.10.005.

Hayflick L, Moorhead PS. The serial cultivation of human diploid cell strains. Exp Cell Res. 1961;25(3):585–621. https://doi.org/10.1016/0014-4827(61)90192-6.

de Magalhães JP, Passos JF. Stress, cell senescence and organismal ageing. Mech Ageing Dev. 2018;170:2–9. https://doi.org/10.1016/j.mad.2017.07.001.

Rhinn M, Ritschka B, Keyes WM. Cellular senescence in development, regeneration and disease. Development. 2019;146(20). https://doi.org/10.1242/dev.151837.

Demaria M, Ohtani N, Youssef SA, Rodier F, Toussaint W, Mitchell JR, et al. An essential role for senescent cells in optimal wound healing through secretion of PDGF-AA. Dev Cell. 2014;31(6):722–33. https://doi.org/10.1016/j.devcel.2014.11.012.

Lee S, Schmitt CA. The dynamic nature of senescence in cancer. Nat Cell Biol. 2019;21(1):94–101. https://doi.org/10.1038/s41556-018-0249-2.

Ogrodnik M, Miwa S, Tchkonia T, Tiniakos D, Wilson CL, Lahat A, et al. Cellular senescence drives age-dependent hepatic steatosis. Nat Commun. 2017;8(1):15691. https://doi.org/10.1038/ncomms15691.

Schafer MJ, White TA, Iijima K, Haak AJ, Ligresti G, Atkinson EJ, et al. Cellular senescence mediates fibrotic pulmonary disease. Nat Commun. 2017;8(1):14532. https://doi.org/10.1038/ncomms14532.

Aguayo-Mazzucato C, Andle J, Lee TB Jr, Midha A, Talemal L, Chipashvili V, et al. Acceleration of beta cell aging determines diabetes and Senolysis improves disease outcomes. Cell Metab. 2019;30(1):129–42 e124. https://doi.org/10.1016/j.cmet.2019.05.006.

Baker DJ, Petersen RC. Cellular senescence in brain aging and neurodegenerative diseases: evidence and perspectives. J Clin Invest. 2018;128(4):1208–16. https://doi.org/10.1172/JCI95145.

Johmura Y, Yamanaka T, Omori S, Wang T-W, Sugiura Y, Matsumoto M, et al. Senolysis by glutaminolysis inhibition ameliorates various age-associated disorders. Science. 2021;371(6526):265–70. https://doi.org/10.1126/science.abb5916.

Zhang P, Kishimoto Y, Grammatikakis I, Gottimukkala K, Cutler RG, Zhang S, et al. Senolytic therapy alleviates Abeta-associated oligodendrocyte progenitor cell senescence and cognitive deficits in an Alzheimer’s disease model. Nat Neurosci. 2019;22(5):719–28. https://doi.org/10.1038/s41593-019-0372-9.

van Deursen JM. The role of senescent cells in ageing. Nature. 2014;509(7501):439–46. https://doi.org/10.1038/nature13193.

Noren Hooten N, Evans MK. Techniques to induce and quantify cellular senescence. JoVE. 2017:e55533.

He S, Sharpless NE. Senescence in health and disease. Cell. 2017;169(6):1000–11. https://doi.org/10.1016/j.cell.2017.05.015.

Coppe JP, Patil CK, Rodier F, Sun Y, Munoz DP, Goldstein J, et al. Senescence-associated secretory phenotypes reveal cell-nonautonomous functions of oncogenic RAS and the p53 tumor suppressor. PLoS Biol. 2008;6(12):2853–68. https://doi.org/10.1371/journal.pbio.0060301.

Kuilman T, Michaloglou C, Vredeveld LC, Douma S, van Doorn R, Desmet CJ, et al. Oncogene-induced senescence relayed by an interleukin-dependent inflammatory network. Cell. 2008;133(6):1019–31. https://doi.org/10.1016/j.cell.2008.03.039.

Chien Y, Scuoppo C, Wang X, Fang X, Balgley B, Bolden JE, et al. Control of the senescence-associated secretory phenotype by NF-kappaB promotes senescence and enhances chemosensitivity. Genes Dev. 2011;25(20):2125–36. https://doi.org/10.1101/gad.17276711.

Freund A, Patil CK, Campisi J. p38MAPK is a novel DNA damage response-independent regulator of the senescence-associated secretory phenotype. EMBO J. 2011;30(8):1536–48. https://doi.org/10.1038/emboj.2011.69.

Herranz N, Gallage S, Mellone M, Wuestefeld T, Klotz S, Hanley CJ, et al. mTOR regulates MAPKAPK2 translation to control the senescence-associated secretory phenotype. Nat Cell Biol. 2015;17(9):1205–17. https://doi.org/10.1038/ncb3225.

Laberge RM, Sun Y, Orjalo AV, Patil CK, Freund A, Zhou L, et al. MTOR regulates the pro-tumorigenic senescence-associated secretory phenotype by promoting IL1A translation. Nat Cell Biol. 2015;17(8):1049–61. https://doi.org/10.1038/ncb3195.

Sharpless NE, Sherr CJ. Forging a signature of in vivo senescence. Nat Rev Cancer. 2015;15(7):397–408. https://doi.org/10.1038/nrc3960.

Hernandez-Segura A, de Jong TV, Melov S, Guryev V, Campisi J, Demaria M. Unmasking transcriptional heterogeneity in senescent cells. Curr Biol. 2017;27(17):2652–60 e2654. https://doi.org/10.1016/j.cub.2017.07.033.

Casella G, Munk R, Kim KM, Piao Y, De S, Abdelmohsen K, et al. Transcriptome signature of cellular senescence. Nucleic Acids Res. 2019;47(14):7294–305. https://doi.org/10.1093/nar/gkz555.

Basisty N, Kale A, Jeon OH, Kuehnemann C, Payne T, Rao C, et al. A proteomic atlas of senescence-associated secretomes for aging biomarker development. PLoS Biol. 2020;18(1):e3000599. https://doi.org/10.1371/journal.pbio.3000599.

Avelar RA, Ortega JG, Tacutu R, Tyler EJ, Bennett D, Binetti P, et al. A multidimensional systems biology analysis of cellular senescence in aging and disease. Genome Biol. 2020;21(1):91. https://doi.org/10.1186/s13059-020-01990-9.

Song WM, Agrawal P, Von Itter R, Fontanals-Cirera B, Wang M, Zhou X, et al. Network models of primary melanoma microenvironments identify key melanoma regulators underlying prognosis. Nat Commun. 2021;12(1):1214. https://doi.org/10.1038/s41467-021-21457-0.

Wang Q, Zhang Y, Wang M, Song WM, Shen Q, McKenzie A, et al. The landscape of multiscale transcriptomic networks and key regulators in Parkinson’s disease. Nat Commun. 2019;10(1):5234. https://doi.org/10.1038/s41467-019-13144-y.

Wang M, Li A, Sekiya M, Beckmann ND, Quan X, Schrode N, et al. Transformative network modeling of multi-omics data reveals detailed circuits, key regulators, and potential therapeutics for Alzheimer’s disease. Neuron. 2020;109(2):257-272.e14. https://doi.org/10.1016/j.neuron.2020.11.002.

Song WM, Zhang B. Multiscale embedded gene co-expression network analysis. PLoS Comput Biol. 2015;11(11):e1004574. https://doi.org/10.1371/journal.pcbi.1004574.

Robinson MD, McCarthy DJ, Smyth GK. edgeR: a bioconductor package for differential expression analysis of digital gene expression data. Bioinformatics. 2010;26(1):139–40. https://doi.org/10.1093/bioinformatics/btp616.

Tumminello M, Aste T, Di Matteo T, Mantegna RN. A tool for filtering information in complex systems. Proc Natl Acad Sci U S A. 2005;102(30):10421–6. https://doi.org/10.1073/pnas.0500298102.

Yu G, Wang LG, Han Y, He QY. clusterProfiler: an R package for comparing biological themes among gene clusters. Omics. 2012;16(5):284–7. https://doi.org/10.1089/omi.2011.0118.

Franzen O, Gan LM, Bjorkegren JLM. PanglaoDB: a web server for exploration of mouse and human single-cell RNA sequencing data. Database. 2019;2019. https://doi.org/10.1093/database/baz046.

Gu Z, Eils R, Schlesner M. Complex heatmaps reveal patterns and correlations in multidimensional genomic data. Bioinformatics. 2016;32(18):2847–9. https://doi.org/10.1093/bioinformatics/btw313.

Li M, Santpere G, Imamura Kawasawa Y, Evgrafov OV, Gulden FO, Pochareddy S, et al. Integrative functional genomic analysis of human brain development and neuropsychiatric risks. Science. 2018;362(6420). https://doi.org/10.1126/science.aat7615.

Stuart T, Butler A, Hoffman P, Hafemeister C, Papalexi E, Mauck WM 3rd, et al. Comprehensive integration of single-cell data. Cell. 2019;177(7):1888–902 e1821. https://doi.org/10.1016/j.cell.2019.05.031.

Guo J, Grow EJ, Mlcochova H, Maher GJ, Lindskog C, Nie X, et al. The adult human testis transcriptional cell atlas. Cell Res. 2018;28(12):1141–57. https://doi.org/10.1038/s41422-018-0099-2.

Baron M, Veres A, Wolock SL, Faust AL, Gaujoux R, Vetere A, et al. A single-cell transcriptomic map of the human and mouse pancreas reveals inter- and intra-cell population structure. Cell Syst. 2016;3(4):346–60 e344. https://doi.org/10.1016/j.cels.2016.08.011.

Madissoon E, Wilbrey-Clark A, Miragaia RJ, Saeb-Parsy K, Mahbubani KT, Georgakopoulos N, et al. scRNA-seq assessment of the human lung, spleen, and esophagus tissue stability after cold preservation. Genome Biol. 2019;21(1):1. https://doi.org/10.1186/s13059-019-1906-x.

Jin S, Guerrero-Juarez CF, Zhang L, Chang I, Ramos R, Kuan CH, et al. Inference and analysis of cell-cell communication using CellChat. Nat Commun. 2021;12(1):1088. https://doi.org/10.1038/s41467-021-21246-9.

Maynard KR, Collado-Torres L, Weber LM, Uytingco C, Barry BK, Williams SR, et al. Transcriptome-scale spatial gene expression in the human dorsolateral prefrontal cortex. Nat Neurosci. 2021;24(3):425–36. https://doi.org/10.1038/s41593-020-00787-0.

Hafemeister C, Satija R. Normalization and variance stabilization of single-cell RNA-seq data using regularized negative binomial regression. Genome Biol. 2019;20(1):296. https://doi.org/10.1186/s13059-019-1874-1.

Subramanian A, Tamayo P, Mootha VK, Mukherjee S, Ebert BL, Gillette MA, et al. Gene set enrichment analysis: a knowledge-based approach for interpreting genome-wide expression profiles. Proc Natl Acad Sci. 2005;102(43):15545–50. https://doi.org/10.1073/pnas.0506580102.

Kiss T, Nyul-Toth A, Balasubramanian P, Tarantini S, Ahire C, DelFavero J, et al. Single-cell RNA sequencing identifies senescent cerebromicrovascular endothelial cells in the aged mouse brain. Geroscience. 2020;42(2):429–44. https://doi.org/10.1007/s11357-020-00177-1.

Korotkevich G, Sukhov V, Budin N, Shpak B, Artyomov MN, Sergushichev A. Fast gene set enrichment analysis. bioRxiv. 2021:060012.

Consortium GT. The genotype-tissue expression (GTEx) project. Nat Genet. 2013;45:580–5.

Consortium GT. Human genomics. The genotype-tissue expression (GTEx) pilot analysis: multitissue gene regulation in humans. Science. 2015;348(6235):648–60. https://doi.org/10.1126/science.1262110.

Keen JC, Moore HM. The genotype-tissue expression (GTEx) project: linking clinical data with molecular analysis to advance personalized medicine. Journal of Personalized Medicine. 2015;5(1):22–9. https://doi.org/10.3390/jpm5010022.

Brown JP, Wei W, Sedivy JM. Bypass of senescence after disruption of p21CIP1/WAF1 gene in normal diploid human fibroblasts. Science. 1997;277(5327):831–4. https://doi.org/10.1126/science.277.5327.831.

Sebastian T, Malik R, Thomas S, Sage J, Johnson PF. C/EBPbeta cooperates with RB:E2F to implement Ras(V12)-induced cellular senescence. EMBO J. 2005;24(18):3301–12. https://doi.org/10.1038/sj.emboj.7600789.

Kortlever RM, Higgins PJ, Bernards R. Plasminogen activator inhibitor-1 is a critical downstream target of p53 in the induction of replicative senescence. Nat Cell Biol. 2006;8(8):877–84. https://doi.org/10.1038/ncb1448.

Ohtani N, Zebedee Z, Huot TJ, Stinson JA, Sugimoto M, Ohashi Y, et al. Opposing effects of Ets and id proteins on p16INK4a expression during cellular senescence. Nature. 2001;409(6823):1067–70. https://doi.org/10.1038/35059131.

Jun JI, Lau LF. The matricellular protein CCN1 induces fibroblast senescence and restricts fibrosis in cutaneous wound healing. Nat Cell Biol. 2010;12(7):676–85. https://doi.org/10.1038/ncb2070.

Martinez-Zamudio RI, Roux PF, de Freitas J, Robinson L, Dore G, Sun B, et al. AP-1 imprints a reversible transcriptional programme of senescent cells. Nat Cell Biol. 2020;22(7):842–55. https://doi.org/10.1038/s41556-020-0529-5.

Saini Y, Chen J, Patial S. The Tristetraprolin family of RNA-binding proteins in cancer: progress and future prospects. Cancers. 2020;12(6). https://doi.org/10.3390/cancers12061539.

Soliman MA, Berardi P, Pastyryeva S, Bonnefin P, Feng X, Colina A, et al. ING1a expression increases during replicative senescence and induces a senescent phenotype. Aging Cell. 2008;7(6):783–94. https://doi.org/10.1111/j.1474-9726.2008.00427.x.

Di Micco R, Krizhanovsky V, Baker D, d'Adda di Fagagna F. Cellular senescence in ageing: from mechanisms to therapeutic opportunities. Nat Rev Mol Cell Biol. 2021;22(2):75–95. https://doi.org/10.1038/s41580-020-00314-w.

Craig RW. MCL1 provides a window on the role of the BCL2 family in cell proliferation, differentiation and tumorigenesis. Leukemia. 2002;16(4):444–54. https://doi.org/10.1038/sj.leu.2402416.

Tonnessen-Murray CA, Lozano G, Jackson JG. The regulation of cellular functions by the p53 protein: cellular senescence. Cold Spring Harb Perspect Med. 2017;7(2). https://doi.org/10.1101/cshperspect.a026112.

Li Q, Tang L, Roberts PC, Kraniak JM, Fridman AL, Kulaeva OI, et al. Interferon regulatory factors IRF5 and IRF7 inhibit growth and induce senescence in immortal Li-Fraumeni fibroblasts. Mol Cancer Res. 2008;6(5):770–84. https://doi.org/10.1158/1541-7786.MCR-07-0114.

Wysk M, Yang DD, Lu H-T, Flavell RA, Davis RJ. Requirement of mitogen-activated protein kinase kinase 3 (MKK3) for tumor necrosis factor-induced cytokine expression. Proc Natl Acad Sci. 1999;96(7):3763–8. https://doi.org/10.1073/pnas.96.7.3763.

Wotton SF, Blyth K, Kilbey A, Jenkins A, Terry A, Bernardin-Fried F, et al. RUNX1 transformation of primary embryonic fibroblasts is revealed in the absence of p53. Oncogene. 2004;23(32):5476–86. https://doi.org/10.1038/sj.onc.1207729.

Cui H, Kong Y, Xu M, Zhang H. Notch3 functions as a tumor suppressor by controlling cellular senescence. Cancer Res. 2013;73(11):3451–9. https://doi.org/10.1158/0008-5472.CAN-12-3902.

Chatsirisupachai K, Palmer D, Ferreira S, de Magalhaes JP. A human tissue-specific transcriptomic analysis reveals a complex relationship between aging, cancer, and cellular senescence. Aging Cell. 2019;18:e13041.

Sturmlechner I, Zhang C, Sine CC, van Deursen EJ, Jeganathan KB, Hamada N, et al. p21 produces a bioactive secretome that places stressed cells under immunosurveillance. Science. 2021;374:eabb3420.

Lee BY, Han JA, Im JS, Morrone A, Johung K, Goodwin EC, et al. Senescence-associated beta-galactosidase is lysosomal beta-galactosidase. Aging Cell. 2006;5(2):187–95. https://doi.org/10.1111/j.1474-9726.2006.00199.x.

Cho SJ, Rossi A, Jung YS, Yan W, Liu G, Zhang J, et al. Ninjurin1, a target of p53, regulates p53 expression and p53-dependent cell survival, senescence, and radiation-induced mortality. Proc Natl Acad Sci U S A. 2013;110(23):9362–7. https://doi.org/10.1073/pnas.1221242110.

Zemskova M, Lilly MB, Lin YW, Song JH, Kraft AS. p53-dependent induction of prostate cancer cell senescence by the PIM1 protein kinase. Mol Cancer Res. 2010;8(8):1126–41. https://doi.org/10.1158/1541-7786.MCR-10-0174.

Musi N, Valentine JM, Sickora KR, Baeuerle E, Thompson CS, Shen Q, et al. Tau protein aggregation is associated with cellular senescence in the brain. Aging Cell. 2018;17(6):e12840. https://doi.org/10.1111/acel.12840.

Burd CE, Sorrentino JA, Clark KS, Darr DB, Krishnamurthy J, Deal AM, et al. Monitoring tumorigenesis and senescence in vivo with a p16(INK4a)-luciferase model. Cell. 2013;152(1-2):340–51. https://doi.org/10.1016/j.cell.2012.12.010.

Zezula J, Casaccia-Bonnefil P, Ezhevsky SA, Osterhout DJ, Levine JM, Dowdy SF, et al. p21cip1 is required for the differentiation of oligodendrocytes independently of cell cycle withdrawal. EMBO Rep. 2001;2(1):27–34. https://doi.org/10.1093/embo-reports/kve008.

Munoz-Espin D, Canamero M, Maraver A, Gomez-Lopez G, Contreras J, Murillo-Cuesta S, et al. Programmed cell senescence during mammalian embryonic development. Cell. 2013;155(5):1104–18. https://doi.org/10.1016/j.cell.2013.10.019.

Storer M, Mas A, Robert-Moreno A, Pecoraro M, Ortells MC, Di Giacomo V, et al. Senescence is a developmental mechanism that contributes to embryonic growth and patterning. Cell. 2013;155(5):1119–30. https://doi.org/10.1016/j.cell.2013.10.041.

Minamino T, Miyauchi H, Yoshida T, Ishida Y, Yoshida H, Komuro I. Endothelial cell senescence in human atherosclerosis: role of telomere in endothelial dysfunction. Circulation. 2002;105(13):1541–4. https://doi.org/10.1161/01.CIR.0000013836.85741.17.

Schmid N, Flenkenthaler F, Stockl JB, Dietrich KG, Kohn FM, Schwarzer JU, et al. Insights into replicative senescence of human testicular peritubular cells. Sci Rep. 2019;9(1):15052. https://doi.org/10.1038/s41598-019-51380-w.

Lee KE, Bar-Sagi D. Oncogenic KRas suppresses inflammation-associated senescence of pancreatic ductal cells. Cancer Cell. 2010;18(5):448–58. https://doi.org/10.1016/j.ccr.2010.10.020.

Bryant AG, Hu M, Carlyle BC, Arnold SE, Frosch MP, Das S, et al. Cerebrovascular senescence is associated with tau pathology in Alzheimer’s disease. Front Neurol. 2020;11:575953. https://doi.org/10.3389/fneur.2020.575953.

Bussian TJ, Aziz A, Meyer CF, Swenson BL, van Deursen JM, Baker DJ. Clearance of senescent glial cells prevents tau-dependent pathology and cognitive decline. Nature. 2018;562(7728):578–82. https://doi.org/10.1038/s41586-018-0543-y.

Bhat R, Crowe EP, Bitto A, Moh M, Katsetos CD, Garcia FU, et al. Astrocyte senescence as a component of Alzheimer's disease. PLoS One. 2012;7(9):e45069. https://doi.org/10.1371/journal.pone.0045069.

Nguyen QH, Pervolarakis N, Nee K, Kessenbrock K. Experimental considerations for single-cell RNA sequencing approaches. Front Cell Dev Biol. 2018;6:108. https://doi.org/10.3389/fcell.2018.00108.