Distinct pools of CENP-A and CENP-C support unique phases of centromere assembly in spermatogenesis

Abstract The centromere is the chromosomal site of kinetochore assembly, defined by the histone H3 variant CENP-A. Each cell cycle, the assembly and maintenance of CENP-A is functionally critical for chromosome segregation. In Drosophila male meiosis, CID (fly CENP-A) is assembled in two phases; prophase of meiosis I and post-meiosis II. Here we investigate the dynamics of the assembly components CAL1 and CENP-C in prophase I and determine the requirements for the second assembly phase. In early prophase I, CENP-C functions with CAL1 to maintain the centromere. In late prophase I, CAL1 is undetectable at centromeres and CENP-C no longer functions in centromere maintenance. Instead CENP-C is critical for meiotic kinetochore recruitment and function. This CENP-C pool also functions in CID assembly post-meiosis II, which is independent of CAL1. In addition to different functional pools of CENP-C, distinct pools of CID protein persist in the male germline, and the synthesis of each pool is uncoupled from its cell cycle deposition timing. Competing Interest Statement The authors have declared no competing interest.