tetano
Editor, Senior Moderator
J Biol Chem. 2012 Nov 13. [Epub ahead of print]
Assembly of subtype 1 influenza neuraminidase is driven by both the transmembrane and head domains.
da Silva DV, Nordholm J, Madjo U, Pfeiffer A, Daniels R.
Source
Stockholm University, Sweden.
Abstract
Neuraminidase (NA) is one of the two major influenza surface antigens and the main influenza drug target. Although NA has been well-characterized and thought to function as a tetramer, the role of the transmembrane domain (TMD) in promoting proper NA assembly has not been systematically studied. Here, we demonstrate that in the absence of the TMD, NA is synthesized and transported in a predominantly inactive state. Substantial activity was rescued by progressive truncations of the stalk domain suggesting the TMD contributes to NA maturation by tethering the stalk to the membrane. To analyze how the TMD supports NA assembly, the TMD was examined by itself. The NA TMD formed a homo-tetramer and efficiently trafficked to the plasma membrane indicating the TMD and enzymatic head domain drive assembly together through matching oligomeric states. In support of this, an unrelated strong oligomeric TMD rescued almost full NA activity, whereas the weak oligomeric mutant of this TMD restored only half of wild type activity. These data illustrate that a large soluble domain can force assembly with a poorly compatible TMD, however optimal assembly requires coordinated oligomerization between the TMD and the soluble domain.
PMID:
23150659
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/23150659
Assembly of subtype 1 influenza neuraminidase is driven by both the transmembrane and head domains.
da Silva DV, Nordholm J, Madjo U, Pfeiffer A, Daniels R.
Source
Stockholm University, Sweden.
Abstract
Neuraminidase (NA) is one of the two major influenza surface antigens and the main influenza drug target. Although NA has been well-characterized and thought to function as a tetramer, the role of the transmembrane domain (TMD) in promoting proper NA assembly has not been systematically studied. Here, we demonstrate that in the absence of the TMD, NA is synthesized and transported in a predominantly inactive state. Substantial activity was rescued by progressive truncations of the stalk domain suggesting the TMD contributes to NA maturation by tethering the stalk to the membrane. To analyze how the TMD supports NA assembly, the TMD was examined by itself. The NA TMD formed a homo-tetramer and efficiently trafficked to the plasma membrane indicating the TMD and enzymatic head domain drive assembly together through matching oligomeric states. In support of this, an unrelated strong oligomeric TMD rescued almost full NA activity, whereas the weak oligomeric mutant of this TMD restored only half of wild type activity. These data illustrate that a large soluble domain can force assembly with a poorly compatible TMD, however optimal assembly requires coordinated oligomerization between the TMD and the soluble domain.
PMID:
23150659
[PubMed - as supplied by publisher]
Free full text
http://www.ncbi.nlm.nih.gov/pubmed/23150659