Pyronin Y  (Synonyms: Pyronine G; C.I. 45005)

Pyronin Y (Pyronine G) is a cationic dye that intercalates RNA and has been used to target cell structures including RNA, DNA and organelles. Pyronin Y forms fluorescent complexes with double-stranded nucleic acids (especially RNA) enabling semi-quantitative analysis of cellular RNA. Pyronin Y can be used to identify specific RNA subspecies of ribonuclear proteins complexes in live cells^[1][2][5].

Pyronin Y forms fluorescent complexes with double-stranded nucleic acids, especially RNA, enabling semi-quantitative analysis of cellular RNA in flow cytometry, to estimate the RNA content per cell in formalin fixed EL4 leukosis tumor cells, enzyme dispersed R3327-G rat prostatic adenocarcinoma cells, mouse spleen cells stimulated with concanavalin A, and human peripheral blood lymphocytes stimulated with phytohemagglutinin^[1].
A fluorescent staining procedure based on pyronin Y is described. The technique has been used to stain RNA in human reticulocytes for subsequent flow analysis and sorting^[2].
In viable cells this dye also accumulates in mitochondria. At a concentration of 1.7 to 3.3 μM, pyronin Y is localized almost exclusively in mitochondria of cultured cells, similar to another mitochondria! probe, rhodamine 123. At that concentration PY is not toxic but suppressed cell growth, arresting cells^[3].
Pyronin Y has long been used, in combination with other dyes such as Methyl Green, as a differential stain for nucleic acids in paraffin tissue sections. In sections stained with Methyl Green-pyronin Y, red blood cells, elastic fibre of blood vessels, zymogen granules of pancreatic acinar cells, surface membrane of heptocytes and kidney tubular cells showed strikingly strong green and/or red fluorescence, while the nuclei of cells appeared non-fluorescent^[4].
Pyronin Y binds to double stranded RNA (dsRNA) including messenger RNA (mRNA), transfer RNA (tRNA) and ribosomal RNA (rRNA)^[5].

MCE has not independently confirmed the accuracy of these methods. They are for reference only.

302.80

Solid

C₁₇H₁₉ClN₂O

92-32-0

CN(C1=CC2=[O+]C3=C(C=CC(N(C)C)=C3)C=C2C=C1)C.[Cl-]

Room temperature in continental US; may vary elsewhere.

-20°C, sealed storage, away from moisture and light

*In solvent : -80°C, 6 months; -20°C, 1 month (sealed storage, away from moisture and light)

• [1]. Pollack A, et al. Flow cytometric analysis of RNA content in different cell populations using pyronin Yand methyl green. Cytometry. 1982 Jul;3(1):28-35.  [Content Brief]

  [2]. Tanke HJ, et al. Flow cytometry of human reticulocytes based on RNA fluorescence. Cytometry. 1981 Mar;1(5):313-20.  [Content Brief]

  [3]. Darzynkiewicz Z, et al. Cytostatic and cytotoxic properties of pyronin Y: relation to mitochondrial localization of the dye and its interaction with RNA. Cancer Res. 1986 Nov;46(11):5760-6.  [Content Brief]

  [4]. Li B, et al. Pyronin Y as a fluorescent stain for paraffin sections. Histochem J. 2002 Jun-Jul;34(6-7):299-303.  [Content Brief]

  [5]. Laura M Andrews, et al. Spectral phasor analysis of Pyronin Y labeled RNA microenvironments in living cells. Biomed Opt Express. 2013 Jan 1;4(1):171-7.  [Content Brief]