Isolation of centrosomes from Spisula solidissima oocytes

Area of Science:

• Cell Biology
• Molecular Biology
• Biochemistry

Background:

• Centrosomes are crucial for microtubule organization and cell division.
• Previous methods for centrosome isolation were limited in scale and accessibility.
• Understanding centrosome composition and function requires robust biochemical and structural analysis techniques.

Purpose of the Study:

• To describe a scalable method for isolating centrosomes from surf clam (S. solidissima) oocytes.
• To enable year-round biochemical and structural studies of centrosomes.
• To facilitate the identification of novel centrosome proteins and elucidate molecular mechanisms of centrosome function.

Main Methods:

• Parthenogenetic activation of surf clam oocytes.
• Preparation of oocyte lysates and storage at -80°C.
• Sucrose-density gradient centrifugation for centrosome purification (3000–4000-fold).
• Storage of isolated centrosomes in high sucrose media at -80°C.

Main Results:

• Scalable preparation of up to 2 liters of lysate per person during oocyte availability (June-August).
• Obtained 2–3 x 10^6 centrosomes per ml of frozen lysate with high purity.
• Isolated centrosomes retain microtubule nucleation potential after long-term storage.
• Yielded 420–600 micrograms of centrosome protein daily, with potential for 20–40 mg annually per individual.
• Provided sufficient centrosome protein for antibody generation and protein sequencing.

Conclusions:

• The surf clam oocyte system provides a convenient and scalable source for centrosome isolation.
• This method supports combined structural and biochemical approaches for centrosome research.
• Enables detailed analysis of centrosome composition, microtubule nucleation, and assembly mechanisms.