Terno, a cyclin-interacting protein regulating meiotic exit and sperm differentiation in Drosophila.

Terno regulates meiotic exit and sperm differentiation in Drosophila by controlling cyclin degradation, with mutants showing extra meiotic divisions and sperm defects.

• Why it matters: Understanding how meiosis and sperm development are precisely regulated is crucial for insights into fertility and reproductive biology, especially since deviations can cause infertility.
• What they did: Researchers identified the terno (teo) gene, which interacts with cyclins A and B, Fizzy, and APC/C components, and demonstrated that teo mutants have elevated cyclin levels and defective sperm maturation.
• The result: Downregulating cyclins rescues the mutant phenotypes, indicating Teo promotes cyclin degradation to regulate meiotic exit and sperm development, revealing a key control point in Drosophila spermatogenesis.