Abstract
The fungal preprotein translocase of the mitochondrial outer membrane (TOM complex) comprises import receptors Tom70, Tom20, and Tom22, import channel Tom40, and small Tom proteins Tom5, Tom6, and Tom7, which regulate TOM complex assembly. These components are conserved in mammals; unlike the other components, however, Tom5 and Tom6 remain unidentified in mammals. We immuno-isolated the TOM complex from HeLa cells expressing hTom22-FLAG and identified the human counterparts of Tom5 and Tom6, together with the other components including Tom7. These small Tom proteins are associated with Tom40 in the TOM complex. Knockdown of Tom7, but not Tom5 and Tom6, strongly compromised stability of the TOM complex. Conversely, knockdown of hTom40 decreased the level of all small Tom proteins. Matrix import of preprotein was affected by double knockdown of any combination of small Tom proteins. These results indicate that human small Tom proteins maintain the structural integrity of the TOM complex.
| Original language | English |
|---|---|
| Pages (from-to) | 958-963 |
| Number of pages | 6 |
| Journal | Biochemical and Biophysical Research Communications |
| Volume | 369 |
| Issue number | 3 |
| DOIs | |
| Publication status | Published - May 9 2008 |
Fingerprint
All Science Journal Classification (ASJC) codes
- Biochemistry
- Biophysics
- Molecular Biology
Cite this
Identification of Tom5 and Tom6 in the preprotein translocase complex of human mitochondrial outer membrane. / Kato, Hiroki; Mihara, Katsuyoshi.
In: Biochemical and Biophysical Research Communications, Vol. 369, No. 3, 09.05.2008, p. 958-963.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Identification of Tom5 and Tom6 in the preprotein translocase complex of human mitochondrial outer membrane
AU - Kato, Hiroki
AU - Mihara, Katsuyoshi
PY - 2008/5/9
Y1 - 2008/5/9
N2 - The fungal preprotein translocase of the mitochondrial outer membrane (TOM complex) comprises import receptors Tom70, Tom20, and Tom22, import channel Tom40, and small Tom proteins Tom5, Tom6, and Tom7, which regulate TOM complex assembly. These components are conserved in mammals; unlike the other components, however, Tom5 and Tom6 remain unidentified in mammals. We immuno-isolated the TOM complex from HeLa cells expressing hTom22-FLAG and identified the human counterparts of Tom5 and Tom6, together with the other components including Tom7. These small Tom proteins are associated with Tom40 in the TOM complex. Knockdown of Tom7, but not Tom5 and Tom6, strongly compromised stability of the TOM complex. Conversely, knockdown of hTom40 decreased the level of all small Tom proteins. Matrix import of preprotein was affected by double knockdown of any combination of small Tom proteins. These results indicate that human small Tom proteins maintain the structural integrity of the TOM complex.
AB - The fungal preprotein translocase of the mitochondrial outer membrane (TOM complex) comprises import receptors Tom70, Tom20, and Tom22, import channel Tom40, and small Tom proteins Tom5, Tom6, and Tom7, which regulate TOM complex assembly. These components are conserved in mammals; unlike the other components, however, Tom5 and Tom6 remain unidentified in mammals. We immuno-isolated the TOM complex from HeLa cells expressing hTom22-FLAG and identified the human counterparts of Tom5 and Tom6, together with the other components including Tom7. These small Tom proteins are associated with Tom40 in the TOM complex. Knockdown of Tom7, but not Tom5 and Tom6, strongly compromised stability of the TOM complex. Conversely, knockdown of hTom40 decreased the level of all small Tom proteins. Matrix import of preprotein was affected by double knockdown of any combination of small Tom proteins. These results indicate that human small Tom proteins maintain the structural integrity of the TOM complex.
UR - http://www.scopus.com/inward/record.url?scp=41149113810&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=41149113810&partnerID=8YFLogxK
U2 - 10.1016/j.bbrc.2008.02.150
DO - 10.1016/j.bbrc.2008.02.150
M3 - Article
C2 - 18331822
AN - SCOPUS:41149113810
VL - 369
SP - 958
EP - 963
JO - Biochemical and Biophysical Research Communications
JF - Biochemical and Biophysical Research Communications
SN - 0006-291X
IS - 3
ER -