Grunnleggende konsepter
Bazooka/Par-3 does not localize to the nuclear envelope or neuromuscular junction in Drosophila, contrary to previous reports.
Sammendrag
The study re-assessed the subcellular localization of the polarity regulator Bazooka/Par-3 (Baz) in Drosophila tissues. Initial immunostaining analysis using various anti-Baz antibodies revealed Baz localization at the nuclear envelope and neuromuscular junction (NMJ), consistent with previous reports. However, further analysis using Baz mutant clones and Baz-GFP fusion proteins showed that the nuclear envelope and NMJ staining patterns were artifacts not reflecting the true Baz localization.
The authors found that the nuclear envelope staining was observed in specific cell types, particularly polyploid cells undergoing endoreduplication. However, this staining persisted even in Baz mutant cells, indicating it was not specific to Baz. Similarly, the NMJ staining was unaffected by Baz RNAi, contradicting the previously reported NMJ phenotypes in Baz mutants.
The authors conclude that Baz does not actually localize to the nuclear envelope or NMJ, and the previously reported localization and functions of Baz at these sites should be interpreted with caution. The study highlights the importance of validating antibody specificity, especially when investigating subcellular localization, and using complementary approaches like tagged fusion proteins to confirm findings.