title: Optimized solubilization of TRIzol-precipitated protein permits Western blotting analysis to maximize data available from brain tissue.
abstract: Techniques simultaneously assessing multiple levels of molecular processing are appealing because molecular signaling underlying complex neural phenomena occurs at complementary levels. The TRIzol method isolates RNA and DNA, but protein retrieval is difficult due to inefficient solubilization of precipitated protein pellets.
  
  
  
  We optimized a buffer for the efficient solubilization of protein from TRIzol-precipitated brain tissue for Western blotting analysis, which was also more effective at directly homogenizing brain tissue than RIPA buffer.
  
  
  
  Protein yield during solubilization, in addition to protein yield via direct homogenization, is increased by optimizing concentrations of chemicals in a standard lysis buffer. Effective incubation parameters for both total protein yield and the analysis of post-translational modifications is remarkably flexible. Importantly, different neural cell types and protein classes are represented in solubilized protein samples. Moreover, we used dissociated mouse brain tissue to isolate microglia from other cell types and successfully resolved cell type-specific proteins from these small and difficult to attain samples.
  
  
  
  Solubilization buffers to date have been comprised primarily of SDS or urea; the data herein demonstrate that components common to lysis buffers can also enhance protein solubilization both after direct homogenization and after precipitation.
  
  
  
  This method is suitable for assessing gene and protein expression from a single brain sample, allowing for a more comprehensive evaluation of neural phenomena while minimizing the number of subjects.
authors.affiliation: Department of Psychology & Neuroscience, Duke University, Durham, NC, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA. Electronic address: akopec@partners.org.
authors.forename: Ashley M
authors.initials: AM
authors.lastname: Kopec
authors.affiliation: Department of Psychology & Neuroscience, Duke University, Durham, NC, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Rivera
authors.affiliation: Department of Psychology & Neuroscience, Duke University, Durham, NC, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lacagnina
authors.affiliation: Department of Psychology & Neuroscience, Duke University, Durham, NC, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
authors.forename: Richa
authors.initials: R
authors.lastname: Hanamsagar
authors.affiliation: Department of Psychology & Neuroscience, Duke University, Durham, NC, USA; Department of Pediatrics, Harvard Medical School, Boston, MA, USA.
authors.forename: Staci D
authors.initials: SD
authors.lastname: Bilbo
mesh_terms: D000818:Animals; D015153:Blotting, Western / Q000379:methods*; D001921:Brain / Q000166:cytology / Q000378:metabolism; D001923:Brain Chemistry; D011232:Chemical Precipitation; D004492:Edetic Acid / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D005260:Female; D006146:Guanidines / Q000737:chemistry; D008297:Male; D008810:Mice, Inbred C57BL; D017628:Microglia / Q000378:metabolism; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D010636:Phenols / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D017207:Rats, Sprague-Dawley; D012965:Sodium Chloride / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012995:Solubility; D013696:Temperature; D013997:Time Factors
chemical_list: D006146:Guanidines; D010636:Phenols; D011506:Proteins; C411644:trizol; D012967:Sodium Dodecyl Sulfate; D012965:Sodium Chloride; D004492:Edetic Acid
keywords: Protein precipitation; Protein solubilization; RIPA buffer; TRIzol; Western blotting