Tetramerization Domain, T1 Domain

2013 ◽  
pp. 2582-2582
2010 ◽  
Vol 298 (3) ◽  
pp. C496-C509 ◽  
Author(s):  
Elyssa D. Burg ◽  
Oleksandr Platoshyn ◽  
Igor F. Tsigelny ◽  
Beatriz Lozano-Ruiz ◽  
Brinda K. Rana ◽  
...  

The activity of voltage-gated K+ (KV) channels plays an important role in regulating pulmonary artery smooth muscle cell (PASMC) contraction, proliferation, and apoptosis. The highly conserved NH2-terminal tetramerization domain (T1) of KV channels is important for proper channel assembly, association with regulatory KV β-subunits, and localization of the channel to the plasma membrane. We recently reported two nonsynonymous mutations (G182R and E211D) in the KCNA5 gene of patients with idiopathic pulmonary arterial hypertension, which localize to the T1 domain of KCNA5. To study the electrophysiological properties and expression patterns of the mutants compared with the wild-type (WT) channel in vitro, we transfected HEK-293 cells with WT KCNA5, G182R, E211D, or the double mutant G182R/E211D channel. The mutants form functional channels; however, whole cell current kinetic differences between WT and mutant channels exist. Steady-state inactivation curves of the G182R and G182R/E211D channels reveal accelerated inactivation; the mutant channels inactivated at more hyperpolarized potentials compared with the WT channel. Channel protein expression was also decreased by the mutations. Compared with the WT channel, which was present in its mature glycosylated form, the mutant channels are present in greater proportion in their immature form in HEK-293 cells. Furthermore, G182R protein level is greatly reduced in COS-1 cells compared with WT. Immunostaining data support the hypothesis that, while WT protein localizes to the plasma membrane, mutant protein is mainly retained in intracellular packets. Overall, these data support a role for the T1 domain in channel kinetics as well as in KCNA5 channel subcellular localization.


2021 ◽  
Author(s):  
Zhen Xu ◽  
Saif Khan ◽  
Nicholas Schnicker ◽  
Sheila A Baker

The Kv family of voltage-gated potassium channels regulate neuronal excitability. The biophysical characteristic of Kv channels can be matched to the needs of different neurons by forming homotetrameric or heterotetrameric channels within one of four subfamilies. The cytoplasmic tetramerization (T1) domain plays a major role in dictating the compatibility of different Kv subunits. The only Kv subfamily missing a representative structure of the T1 domain is the Kv2 family. We used X-ray crystallography to solve the structure of the human Kv2.1 T1 domain. The structure is similar to other T1 domains but surprisingly formed a pentamer instead of a tetramer. In solution the Kv2.1 T1 domain also formed a pentamer as determined with in-line SEC-MALS-SAXS and negative stain EM. The Kv2.1 T1-T1 interface involves electrostatic interactions including a salt bridge formed by the negative charges in a previously described CDD motif, and inter-subunit coordination of zinc. We show that zinc binding is important for stability. In conclusion, the Kv2.1 T1 domain behaves differently from the other Kv T1 domains which may reflect the versatility of Kv2.1, the only Kv subfamily that can assemble with the regulatory KvS subunits and scaffold ER-plasma membrane contacts.


Biochemistry ◽  
2000 ◽  
Vol 39 (34) ◽  
pp. 10347-10352 ◽  
Author(s):  
William R. Kobertz ◽  
Carole Williams ◽  
Christopher Miller
Keyword(s):  

2021 ◽  
Author(s):  
Jin Gao ◽  
Laura Klenow ◽  
Lisa Parsons ◽  
Tahir Malik ◽  
Je-Nie Phue ◽  
...  

Supplementing influenza vaccines with recombinant neuraminidase (rNA) antigens remains a promising approach for improving the suboptimal vaccine efficacy. However, correlations among rNA designs, properties, and protection have not been systematically investigated. Here, we performed a comparative analysis of several rNAs produced using the baculovirus/insect cell system. The rNAs were designed with different tetramerization motifs and NA domains from a recent H1N1 vaccine strain (A/Brisbane/02/2018) and were compared for enzymatic property, antigenicity, stability, and protection in mice. We found that distinct enzymatic properties are associated with rNAs containing the NA head-domain versus the full-ectodomain, formation of higher order rNA oligomers is tetramerization domain-dependent, whereas protective efficacy is more contingent on the combination of the tetramerization and NA domains. Following single-dose immunizations, a rNA possessing the full-ectodomain and the tetramerization motif from the human vasodilator-stimulated phosphoprotein provided much better protection than a rNA with ∼10-fold more enzymatically active molecules that is comprised of the head-domain and the same tetramerization motif. In contrast, these two rNA designs provided comparable protection when the tetramerization motif from the tetrabrachion protein was used instead. These findings demonstrate that individual rNAs should be thoroughly evaluated for vaccine development, as the heterologous domain combination can result in rNAs with similar key attributes but vastly differ in protection. IMPORTANCE For several decades it has been proposed that influenza vaccines could be supplemented with recombinant neuraminidase (rNA) to improve the efficacy. However, some key questions for manufacturing stable and immunogenic rNA remain to be answered. We show here that the tetramerization motifs and NA domains included in the rNA construct design can have a profound impact on the biochemical, immunogenic and protective properties. We also show that the single-dose immunization regimen is more informative for assessing the rNA immune response and protective efficacy, which is surprisingly more dependent on the specific combination of NA and tetramerization domains than common attributes for evaluating NA. Our findings may help to optimize the design of rNAs that can be used to improve or develop influenza vaccines.


2008 ◽  
Vol 105 (43) ◽  
pp. 16426-16431 ◽  
Author(s):  
S. Gordo ◽  
V. Martos ◽  
E. Santos ◽  
M. Menendez ◽  
C. Bo ◽  
...  

2011 ◽  
Vol 100 (3) ◽  
pp. 348a
Author(s):  
Elke Bocksteins ◽  
Evy Mayeur ◽  
Tine Bruyns ◽  
Dirk J. Snyders
Keyword(s):  

PLoS Genetics ◽  
2021 ◽  
Vol 17 (5) ◽  
pp. e1009412
Author(s):  
Seiya Oura ◽  
Takayuki Koyano ◽  
Chisato Kodera ◽  
Yuki Horisawa-Takada ◽  
Makoto Matsuyama ◽  
...  

Meiosis is a cell division process with complex chromosome events where various molecules must work in tandem. To find meiosis-related genes, we screened evolutionarily conserved and reproductive tract-enriched genes using the CRISPR/Cas9 system and identified potassium channel tetramerization domain containing 19 (Kctd19) as an essential factor for meiosis. In prophase I, Kctd19 deficiency did not affect synapsis or the DNA damage response, and chiasma structures were also observed in metaphase I spermatocytes of Kctd19 KO mice. However, spermatocytes underwent apoptotic elimination during the metaphase-anaphase transition. We were able to rescue the Kctd19 KO phenotype with an epitope-tagged Kctd19 transgene. By immunoprecipitation-mass spectrometry, we confirmed the association of KCTD19 with zinc finger protein 541 (ZFP541) and histone deacetylase 1 (HDAC1). Phenotyping of Zfp541 KO spermatocytes demonstrated XY chromosome asynapsis and recurrent DNA damage in the late pachytene stage, leading to apoptosis. In summary, our study reveals that KCTD19 associates with ZFP541 and HDAC1, and that both KCTD19 and ZFP541 are essential for meiosis in male mice.


2013 ◽  
Vol 44 (7) ◽  
pp. 1271-1277 ◽  
Author(s):  
Tadashi Hasegawa ◽  
Hiroko Asanuma ◽  
Jiro Ogino ◽  
Yoshihiko Hirohashi ◽  
Yasuhisa Shinomura ◽  
...  

2002 ◽  
Vol 277 (49) ◽  
pp. 47885-47890 ◽  
Author(s):  
Alex W. Jahng ◽  
Candace Strang ◽  
Don Kaiser ◽  
Thomas Pollard ◽  
Paul Pfaffinger ◽  
...  
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document