Peptide nanoparticle-mediated siRNA transfection can efficiently and specifically knock down gene expression.

<p>(A) Trim75 localizes within spindles in MI (upper) and MII (lower) oocytes. Tubulin is shown in green, trim75 in red, kinetochores in magenta, and DNA in blue. (B) Trim75 staining in control (upper) and TRIM75 siRNA-treated MI oocytes. Trim75 staining significantly decreased after trim75 siRNA treatment. (C) RT-PCR showed that TRIM75 mRNA level significantly decreased after TRIM75 siRNA treatment (arrow), whereas the mRNA levels of the other TRIM family members, TRIM24, TRIM33, and TRIM37, did not change. GAPDH was used as a control. (D) Western blot showed that trim75 significantly decreased after TRIM75 siRNA transfection. β-actin was used as a control. (E) Western blot showed that trim75 also significantly decreased after TRIM75 siRNA microinjection. β-actin was used as a control. (F) Blot quantification showed that trim75 knockdown by transfection is as good as by microinjection. Scale bar, 20 μm.