PUBLICATION

Liver-Enriched Gene 1, a Glycosylated Secretory Protein, Binds to FGFR and Mediates an Anti-stress Pathway to Protect Liver Development in Zebrafish

Authors

Hu, M., Bai, Y., Zhang, C., Liu, F., Cui, Z., Chen, J., Peng, J.

ID

ZDB-PUB-160224-7

Date

2016

Source

PLoS Genetics 12: e1005881 (Journal)

Registered Authors

Chen, Jun, Cui, Zongbin, Hu, Minjie, Liu, Feng, Peng, Jinrong, Zhang, Chunxia

Keywords

Embryos, Liver development, Phenotypes, ERK signaling cascade, Glycosylation, Protein extraction, Zebrafish, Protein secretion

MeSH Terms

Molecular Sequence Data
Zebrafish/embryology*
MAP Kinase Signaling System
Zygote/metabolism
Stress, Physiological*
Mutation/genetics
Receptor, Fibroblast Growth Factor, Type 3/metabolism*
Amino Acid Sequence
Liver/embryology*
Liver/metabolism*
Zebrafish Proteins/chemistry
Zebrafish Proteins/metabolism*
Protein Binding
Base Sequence
Animals
Phosphorylation
Glycosylation
Phenotype

(all 18)

PubMed

26901320 Full text @ PLoS Genet.

Abstract

Unlike mammals and birds, teleost fish undergo external embryogenesis, and therefore their embryos are constantly challenged by stresses from their living environment. These stresses, when becoming too harsh, will cause arrest of cell proliferation, abnormal cell death or senescence. Such organisms have to evolve a sophisticated anti-stress mechanism to protect the process of embryogenesis/organogenesis. However, very few signaling molecule(s) mediating such activity have been identified. liver-enriched gene 1 (leg1) is an uncharacterized gene that encodes a novel secretory protein containing a single domain DUF781 (domain of unknown function 781) that is well conserved in vertebrates. In the zebrafish genome, there are two copies of leg1, namely leg1a and leg1b. leg1a and leg1b are closely linked on chromosome 20 and share high homology, but are differentially expressed. In this report, we generated two leg1a mutant alleles using the TALEN technique, then characterized liver development in the mutants. We show that a leg1a mutant exhibits a stress-dependent small liver phenotype that can be prevented by chemicals blocking the production of reactive oxygen species. Further studies reveal that Leg1a binds to FGFR3 and mediates a novel anti-stress pathway to protect liver development through enhancing Erk activity. More importantly, we show that the binding of Leg1a to FGFR relies on the glycosylation at the 70th asparagine (Asn70 or N70), and mutating the Asn70 to Ala70 compromised Leg1's function in liver development. Therefore, Leg1 plays a unique role in protecting liver development under different stress conditions by serving as a secreted signaling molecule/modulator.

Genes / Markers

Figures

Show all Figures

Expression

Gene	Antibody	Fish	Conditions	Stage	Anatomy	Assay	Figure
bhmt	ab1-bhmt	leg1.1^zju6/zju6	control	Prim-15	liver	IHC	Fig. 3
bhmt	ab1-bhmt	leg1.1^zju6/zju6	radiation	Prim-15	liver	IHC	Fig. 3
fabp10a		leg1.1^zju6/zju6	control	Protruding-mouth	liver	ISH	Fig. 3
fabp10a		leg1.1^zju6/zju6	radiation	Protruding-mouth	liver	ISH	Fig. 3
fabp10a		leg1.1^zju6/zju6	standard conditions	Days 7-13	liver	ISH	Fig. 8
fabp10a		WT	radiation	Protruding-mouth	liver	ISH	Fig. 3
fabp10a		WT	control	Protruding-mouth	liver	ISH	Fig. 3
fabp2		leg1.1^zju6/zju6	radiation	Protruding-mouth	intestine	ISH	Fig. 3
fabp2		leg1.1^zju6/zju6	control	Protruding-mouth	intestine	ISH	Fig. 3
fabp2		WT	control	Protruding-mouth	intestine	ISH	Fig. 3

1 - 10 of 50

Show

Phenotype

Fish	Conditions	Stage	Phenotype	Figure
leg1.1^zju6/zju6	control	Protruding-mouth	liver decreased size, abnormal	Fig. 2
leg1.1^zju6/zju6	standard conditions	Protruding-mouth	liver development process quality, normal	Fig. 1
leg1.1^zju6/zju6	standard conditions	Protruding-mouth	whole organism leg1.2 expression increased amount, abnormal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Day 4	whole organism leg1.2 expression increased amount, abnormal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Day 5	whole organism leg1.2 expression increased amount, abnormal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Days 7-13	whole organism leg1.2 expression increased amount, abnormal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Adult	axis decreased length, abnormal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Adult	liver size, normal	Fig. 8
leg1.1^zju6/zju6	standard conditions	Adult	whole organism decreased life span, abnormal	Fig. 8
leg1.1^zju6/zju6	overcrowding, heat exposure	Protruding-mouth	liver decreased size, abnormal	Fig. 2

1 - 10 of 12

Show

Mutations / Transgenics

Allele	Construct	Type	Affected Genomic Region
fr13Tg	Tg(hsp70l:bmp2b)	Transgenic Insertion
pd1Tg	Tg(hsp70l:dnfgfr1a-EGFP)	Transgenic Insertion
zju6		Indel	leg1.1
zju7		Indel	leg1.1

Human Disease / Model

Sequence Targeting Reagents

Target	Reagent	Reagent Type
leg1.1	TALEN1-leg1.1	TALEN

Fish

Fish
fr13Tg
leg1.1^zju6/zju6
leg1.1^zju6/zju6
leg1.1^zju7/zju7
WT

Antibodies

Name	Type	Antigen Genes	Isotypes	Host Organism
Ab1-bhmt	monoclonal	bhmt		Mouse
Ab1-eif2a	polyclonal	eif2a		Rabbit
Ab1-smad	polyclonal	smad1 smad5 smad9	IgG	Rabbit
Ab2-ddit3	polyclonal			Rabbit
Ab7-hspa5	polyclonal		IgG	Rabbit
Ab7-mapk	polyclonal			Rabbit
Ab11-mapk	monoclonal		IgG	Rabbit

1 - 7 of 7

Show

Orthology

Engineered Foreign Genes

Marker	Marker Type	Name
EGFP	EFG	EGFP

Mapping

Hu et al., 2016 ZDB-PUB-160224-7 PMID:26901320

Liver-Enriched Gene 1, a Glycosylated Secretory Protein, Binds to FGFR and Mediates an Anti-stress Pathway to Protect Liver Development in Zebrafish

Hu et al., 2016

ZDB-PUB-160224-7
PMID:26901320