Table Info

Table 2.

Selected novel fusion proteins derived from hepatitis B virus (HBV) splice variants and their proposed role and/or effect on HBV replication

Splice variant	Novel protein	Size (kDa)	Proposed role/effect on HBV replication	References
Sp1	HBSP	10	Induces apoptosis	[75, 79, 80]
			Prevents apoptosis	[81]
			Associated with higher levels of HBV replication and severe liver fibrosis	[5]
			Limits liver inflammation	[82]
			Interacts with cellular factors	[83–85]
			Induces T-cell responses	[86]
	p21.5	21.5	Inhibits nucleocapsid formation to reduce wild-type HBV replication	[88]
	C-terminal truncated core protein	21	Replaces wild-type core protein	[87]
	C-terminal truncated core protein	21	Contributes to nucleocapsid formation	[1]
	N-terminal truncated pol protein	39	Unknown	[48]
Sp3	Precore-pol	48	Unknown	[9, 89]
Sp3	Core-pol	47	Unknown	[9, 89]
Sp7	HBDSP	15	Acts as a Gal4 activation domain Has transactivation activity on viral genes	[76]
Sp9	Precore-surface	45	Strongly decreases wild-type HBV replication	[89]
	Core-surface	44	Strongly decreases wild-type HBV replication	[89]
	C-terminal truncated pol with new open reading frame	12	Unknown	[89]
	N-terminal truncated pol	50	Unknown	[89]
Sp10	Core-surface	35	Unknown	[78]
Sp13	Pol-surface	43	Replaces large surface protein	[90]
			Prevents secretion of HBsAg	[77]
			Involved in Sp13-mediated suppression of wild-type HBV replication	[77]

HBSP: hepatitis B spliced protein; pol: polymerase; HBDSP: hepatitis B doubly spliced protein; HBsAg: hepatitis B surface antigen

Declarations

Author contributions

LCM: Investigation, Writing—original draft, Writing—review & editing. ML: Writing—review & editing, Supervision. PAR: Conceptualization, Writing—review & editing, Supervision.

Conflicts of interest

PAR has received investigator-initiated industry-funded grants from Gilead. None of this support is relevant to the work in this manuscript. The remaining authors declare no conflicts of interest.

Ethical approval

Not applicable.

Consent to participate

Not applicable.

Consent to publication

Not applicable.

Availability of data and materials

Not applicable.

Funding

LCM, ML and PAR were funded by National Health and Medical Research Council (NHMRC) grant [1145977]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Copyright

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