Your Query returns 3 Accession Numbers:

Query TermAccessionNCBI TaxonidSynonymsPhenotype (OMIM) *
20S proteasomeNM_0803537227CG3422    Pros28    pros28.1    PROS-28.1    alpha4_dm    PROSA-28.1    PROS-Dm28.1   
20S proteasomeNG_0001287227CG9327    pros29    CT26525    PROS-29    alpha3_dm   
20S proteasomeNG_0005587227PRCZ    PSMA5    CG10938    CT30641    alpha5_dm    ProsMA5   

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* OMIM link based on symbol match for human and mouse.

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Text2Knowledge ... Yong Huang 2002