Brain
Whole brain (
30,
52,
53), cerebellum (
54), pons (
52), corpus striatum (
55), myelencephalon (
52), choroid plexus (
306) and astrocytes (
56) express
scgf gene. Neurotoxic agents such as dioxin and methamphetamine up-regulate
scgf gene expression in the mouse embryonic brain (
53) and
c-fos+/+ mouse corpus striatum as compared with
c-fos+/- one (
55), respectively. Cerebellar
scgf gene expression is affected in
wdl (waddles) mouse characterized by hereditary carbonic anhydrase VIII deficiency in the cerebellar Purkinje cells (
54).
Bipotent mouse neuronal cell line, 1C11, is induced to be serotonergic and noradrenergic in the culture with d-cAMP and d-cAMP/DMSO, respectively.
Scgf gene is strikingly down-regulated in both the serotonergic and noradrenergic cells as compared with untreated immature 1C11 cells (
205).
Scgf gene expression is 4-fold down-regulated in the supraoptic nucleus as compared with the total hypothalamus (
241).
Trimethylated histone H3K4 is present within 2kb of transcription start site of
scgf gene, the distribution of which is specific to neuronal nuclei of human prefrontal cortex (
256).
Smarca4/Brg1 is required for differentiation of oligodendrocyte precursor cells, thus severe myelination deficit is seen in Smarca4/Brg1 mutant mice.
Scgf gene expression is up-regulated in oligodendrocyte-enriched optic nerves from Smarca4/Brg1-knockout mice at postnatal day 14 (
461).
Scgf gene expression is down-regulated in rat late-passage olfactory bulb-derived olfactory ensheathing cells (OECs) (
318), mucosa OECs (
319) and native OECs (
320).
Scgf gene expressed in human ES cells, WA-09, is gradually up-regulated along neural differentiation to anterior cerebral cortex (
467,
Neural Stem Cell Institute, Cortecon). When human neural stem/progenitor cells are induced to differentiate on the polystyrene polymer scaffold or to form neurospheres, the differentiated cells up-regulate
scgf gene expression relative to conventional two-dimensional culture controls (
343).
Scgf gene expression is up-regulated in neurons differentiated from NTERA-2/cl.D1 human embryonic teratocarcinoma cells (
187).
SCGF level in normal human cerebrospinal fluid is found to increase with aging (
356).
Visit
Allen Institute for Brain Science where have been accumulated
in situ hybridization images of
scgf gene in
mouse brain (coronal and
sagittal) and
spinal cord (juvenile and adult). SCGF is little detected in the conditioned
medium with compression-injured rat spinal cord (481).
During mouse embryonic development, olfactory epithelium and vomero-nasal organ express higher level of scgfgene than olfactory placode (451).
Eyes
Human spheroid MSCs-derived microvesicles promote mouse 661W retinal photoreceptor cells to secrete SCGF compared to monolayer MSCs-derived miocrovesicles (
544). Retinal MÜller cells secrete SCGF (
584).
Scgf gene is weakly expressed during fetus and diminished during adult in cornea (
57), lens epithelial cells (
58), conjunctiva/Tenon capsule (
59), iris (
60) and trabecular meshwork (
61). In contrast, retina stably expresses
scgf gene (
62-
64), first seen in the lateral neuroblast layer, then in lens lateral neuroblast layer and last in photoreceptor visceral nuclear layer along fetal development, and photoreceptor, horizontal cells, bipolar cells and retinal pigment epithelium of adult retina (
62,
64).
Hfe (histocompatibility leukocyte antigen class I-like protein involved in iron homeostasis) is expressed exclusively in the basal membrane of retinal pigment epithelium (RPE).
Hfe-/-mice develop ferritin accumulation in retina and hyperproliferation of RPE, where
scgf gene is down-regulated as compared with wild type controls (
215).
Three rabbit corneal layers of epithelium, stroma and endothelium are mutually scraped apart and proteins extracted from each layer are analyzed using LC-MS/MS. SCGF peptides are detected only in the endothelium (
210). SCGF is a member of ECM proteins in 3 types of basement membranes from adult human eyes, including inner limiting membrane, retinal blood vessel and lens capsule (
472).
Cyclin D1 binds to
scgf promoter (Chr7:40478877-40478922) in the retina from
cyclin D1-knockin mouse, possibly regulating
scgf gene expression, but retinas from
cyclin D1-knockout (
Ccnd1-/-) mouse show no significant change in
scgf gene expression as compared to wild type controls (
281).
Mouth
Scgfgene expression is up-regulated in the order of posterior nasal ＞ posterior oral ＝ anterior nasal ＞ anterior
oral compartment of E14.5 (soon after palate fusion) mouse palate (506).
Skin
Circadian clock
Per1 gene maintains murine CD34
+α6 integrin
brightPer1
-venus
bright hair follicle epidermal stem cells dormant, where
scgf gene expression is up-regulated relative to the Per1-venus
dim stem cells (
352).
Scgf gene is expressed in neonatal or immature epidermal keratinocytes (
65,
66), and down-regulated in response to TNF-α
(65), EGF or bovine pituitary gland extracts (
66).
Scgf gene expression is up-regulated in the human epidermal keratinocytes immediately after exposure to hyperthermic stress (
414). Human cytomegalovirus infection induces dermal fibroblasts to secrete various cytokines including SCGF for wound healing and angiogenesis (
29). Transgenic mice overexpressing glucocorticoid receptor under control of keratin 5 promoter exhibit resistance to skin carcinogenesis, in which follicular epidermal stem cells (target for carcinogenesis) decrease in both number and clonogenecity, and their
scgf gene expression is significantly down-regulated as compared with wild type mice (
68).
Differentiation of epidermal progenitor cells to keratinocytes down-regulates DNA methyltransferase 1 (
dnmt1) gene expression, along which
scgf gene is somewhat up-regulated and loses methylation (
280). However
dnmt1 knockdown with
dnmt1 shRNA little affects
scgf gene expression.
Scgf is one of signature genes of dermal fibroblasts in the niche harboring embryonic hair follicle stem cells (
Hair-GEL: A Transcriptome Atlas of Embryonic Hair Follicle Stem Cells and Their Niche, Icahn School of Medicine at Mount
Sinai). When mouse live harvested dermal fibroblasts are cultured,
scgf gene expression is significantly down-regulated compared to the level before culture (
485).
SCGF is produced by normal primary dermal fibroblasts (
421). IL-1β-activation down-regulates SCGF production by human fibroblasts from skin (
479).
