Recombinant human parainfluenza 3 virus (HPIV-3) Hemagglutinin-neuraminidase (HN) production starts with isolating the target gene, which encodes the 1-572aa of the HPIV-3 HN protein. This gene is inserted into an expression vector along with an N-terminal 10xHis-tag gene. The positive expression vector is selected and then cultured in the in vitro E.coli expression system. The recombinant proteins are expressed and then harvested from the culture medium. Purification of the protein is typically achieved using affinity chromatography. The recombinant HPIV-3 HN protein's purity is determined by SDS-PAGE, reaching over 85%.
HPIV-3 HN protein is a type II surface glycoprotein that plays a crucial role in the viral life cycle. It is involved in receptor binding, membrane penetration, syncytium formation, and activation of the fusion (F) protein to initiate fusion, which is essential for viral entry into host cells [1-3]. Studies have shown that the HN protein of HPIV-3 recognizes both α2,3- and α2,6-linked sialic acids, which are important for viral attachment and entry into host cells [4]. The HN protein is implicated in triggering fusion and promoting virus-cell interactions through its receptor-binding sites [5]. Furthermore, research has demonstrated that the HN protein, along with the fusion (F) glycoprotein, plays a significant role in inducing a protective immune response following immunization, highlighting its importance as a target for antiviral strategies and vaccine development [6].
References:
[1] M. Porotto, O. Greengard, N. Poltoratskaia, M. Horga, & A. Moscona, Human parainfluenza virus type 3 hn-receptor interaction: effect of 4-guanidino-neu5ac2en on a neuraminidase-deficient variant, Journal of Virology, vol. 75, no. 16, p. 7481-7488, 2001. https://doi.org/10.1128/jvi.75.16.7481-7488.2001
[2] M. Porotto, Z. Salah, I. DeVito, A. Talekar, S. Palmer, R. Xuet al., The second receptor binding site of the globular head of the newcastle disease virus hemagglutinin-neuraminidase activates the stalk of multiple paramyxovirus receptor binding proteins to trigger fusion, Journal of Virology, vol. 86, no. 10, p. 5730-5741, 2012. https://doi.org/10.1128/jvi.06793-11
[3] M. Porotto, M. Murrell, O. Greengard, & A. Moscona, Triggering of human parainfluenza virus 3 fusion protein (f) by the hemagglutinin-neuraminidase (hn) protein: an hn mutation diminishes the rate of f activation and fusion, Journal of Virology, vol. 77, no. 6, p. 3647-3654, 2003. https://doi.org/10.1128/jvi.77.6.3647-3654.2003
[4] K. Fukushima, T. Takahashi, H. Ueyama, M. Takaguchi, S. Itô, K. Oishiet al., Amino acid substitutions contributing to α2,6‐sialic acid linkage binding specificity of human parainfluenza virus type 3 hemagglutinin–neuraminidase, Febs Letters, vol. 589, no. 11, p. 1278-1282, 2015. https://doi.org/10.1016/j.febslet.2015.03.036
[5] M. Porotto, M. Fornabaio, G. Kellogg, & A. Moscona, A second receptor binding site on human parainfluenza virus type 3 hemagglutinin-neuraminidase contributes to activation of the fusionmechanism, Journal of Virology, vol. 81, no. 7, p. 3216-3228, 2007. https://doi.org/10.1128/jvi.02617-06
[6] R. Ray, B. Glaze, & R. Compans, Role of individual glycoproteins of human parainfluenza virus type 3 in the induction of a protective immune response, Journal of Virology, vol. 62, no. 3, p. 783-787, 1988. https://doi.org/10.1128/jvi.62.3.783-787.1988
