GAMMA-BUTYROBETAINE HYDROXYLASE-RELATED (PTHR10696) - mitochondrion

[hattrill]

• PTHR ID & PTN node:
  PTN000075473
  GAMMA-BUTYROBETAINE HYDROXYLASE-RELATED (PTHR10696)

• Sequences with problematic annotation (ID + gene/protein name):
  Block propagation of 'mitochondrion' to FBgn0033830 CG10814

• Type of Issue: Erroneous source or erroneous propagation, or other issue
  Short version: FBgn0033830 CG10814 has no predicted MTS or experimental data supporting mitochondrial localization.

So, for these enzymes things might be a bit more complex, so you might want to review the tree. The above step is 'good enough' for us, but I don't know how it impacts other species.
General consensus is that: "In all mammals studied, BBD (BBH) is localized in the cytosol" (PMID:11802770) (and Reactome: https://reactome.org/PathwayBrowser/#/R-HSA-71262) and this is where carnitine biosynthesis and the step catalysed by BBOX1 (gamma-butyrobetaine hydroxylase 1) occurs.

Flies have 3 BBH genes in flies and 2 of these gene products are mitochondrial:

From L-Carnitine in Drosophila: A Review PMID: 33371457 PMCID: PMC7767417 DOI: 10.3390/antiox9121310
"In the Drosophila genome, there are three paralogous genes (CG14630, CG5321, CG10184) that are considered putative orthologs for the human γ-BBH1 (γ-ButyroBetaine Hydroxylase 1) gene. In a recent study that aimed to identify genes contributing to the functional decline of the Drosophila brain during aging, Laranjeira et al. (PMID:27518101) suggested that the CG10814 gene was the most likely ortholog for the hγ-BBH1 gene, sharing with this the lack of a mitochondrial targeting sequence."

This is supported by what I see:
Based on MitoFates and TargetP prediction, CG5321 (FBgn0030575) and CG14630 (FBgn0014903) possess a mitochondrial targeting sequence (MTS) and have been detected in the mitochondrion in a high-throughput proteomics study (PMID:24070373). CG10814 has no predicted MTS or experimental data supporting mitochondrial localization.

The yeast ortholog AIM17, has been seen in the mitochondrion and has this description "Protein of unknown function; the authentic, non-tagged protein is detected in highly purified mitochondria in high-throughput studies; null mutant displays reduced frequency of mitochondrial genome loss"