4I2Y:
reference: Genetically encoded calcium indicators for multi-color neural activity imaging and combination with optogenetics., Akerboom J, Carreras Calderon N, Tian L, Wabnig S, Prigge M, Tolo J, Gordus A, Orger MB, Severi KE, Macklin JJ, Patel R, Pulver SR, Wardill TJ, Fischer E, Schuler C, Chen TW, Sarkisyan KS, Marvin JS, Bargmann CI, Kim DS, Kugler S, Lagnado L, Hegemann P, Gottschalk A, Schreiter ER, Looger LL, Front Mol Neurosci. 2013;6:2. doi: 10.3389/fnmol.2013.00002. Epub 2013 Mar 4. PMID: 23459413

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