In Search of Zonation Markers to Identify Liver Functional Disorders

Table 2

Current genes used as markers to identify liver zonation.

Zone	Gene symbol	Biological function	Detection methods	Sources	References
Pericentral zones	Cyp1a	CYPs serve to detoxify xenobiotics prior to being drained into the pericentral zone.	Frozen section + immunostaining	Rat anti-CYP1A2 antibody	[15]; [44]
	Cyp3a			Rabbit anti-CYP3A1 antibody, Biotrend, Germany
	Cyp2c			Rat anti-CYP2C6 antibody
	Cyp2e1		Frozen/FFPE section + immunostaining	Rabbit anti-CYP2E1 antibody, Sigma-Aldrich, USA
	Gs	GS catalyzes the condensation of ammonia by converting glutamate to glutamine.	Frozen section + immunostaining	Mouse anti-GS antibody, BD Bioscience, Germany; RNAscope probes: NM 008131, region 103-973; Anti-GS (clone 2B12) antibody, Sigma-Aldrich, USA	[16]
			In situ hybridization
			Western blot
			qRT-PCR
	Axin2	A universal transcriptional target of Wnt/β-catenin signaling is Axin2, whose expression offers a reliable readout of hepatocytes responding to Wnt.	In situ hybridization	RNAscope probes: NM 015732, region 330-1287; Chicken anti-GFP antibody, Abcam ab13970, UK	[6]
			Frozen section + immunostaining (GFP-tag model)
	Tbx3	Tbx3 is another target gene of Wnt signaling, which has been identified as a progenitor marker of hepatocytes.	In situ hybridization	RNAscope probes: NM 198052
Periportal zones	Arg1	Arginase converts L-arginine to L-ornithine and urea, affecting hepatic nitric oxide synthase (NOS) activities by decreasing L-arginine bioavailability.	Frozen section + immunostaining Western blot qRT-PCR	Rabbit anti-arginase-1 antibody, Sigma-Aldrich, USA; Anti-arginase-1 antibody, BD Transduction Laboratories, CA	[17]
	Cps1	CPS is an ATP-dependent enzyme and converts ammonia and carbon dioxide (CO2) to carbamoyl phosphate.	Frozen section + immunostaining qRT-PCR	Rabbit anti-CPS1 antibody, Abcam, UK
	Mfsd2α	Mfsd2a, previously recognized as a protein that maintains blood-brain barrier function, is a periportal zonation marker.	Frozen section + immunostaining (RFP-tag model)	Rabbit anti-RFP antibody, Rockland 600-401-379, USA	[18]

Note: Cyp: cytochrome P450; Gs: glutamine synthetase; Tbx3: T-box transcription factor 3; Arg1: Arginase1; Cps1: carbamoyl phosphate synthase 1; Mfsd2a: major facilitator superfamily domain-containing 2a; FFPE: formalin-fixed paraffin-embedded.