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At least 433 records · Page 24Linked to original sources
PubMed1984

A [14C]2-deoxyglucose analysis of the functional neural pathways of the limbic forebrain in the rat. IV. A pathway from the prefrontal cortical-medial thalamic system to the hypothalamus.

The present study utilized the [14C]2-deoxyglucose (2-DG) cell labeling procedure to characterize a functional pathway from the prefrontal cortex (Pfc) and mediodorsal thalamic nucleus (MD) to the hypothalamus. Rats were injected with 2-DG prior to a 45 min experimental paradigm consisting of alternating 30 s on-off periods of electrical brain stimulation. Standard procedures were utilized for the removal and processing of brain tissue for X-ray autoradiography. In the first phase of this study, stimulation applied to the prefrontal cortex generally yielded a pattern of 2-DG distribution consistent with the findings of classical anatomical studies. Stimulation of the dorsomedial and ventromedial prefrontal cortex or the infralimbic cortex produced the most effective activation of the diencephalon. This activation was primarily limited to MD, with no involvement of any region of the hypothalamus. In the second phase of this study, brain regions activated following stimulation of sites along the rostro-caudal axis of MD were examined. Stimulation of MD resulted in the activation of the nucleus reuniens and other midline and non-specific thalamic nuclei. Stimulation of this nucleus also activated the ventromedial thalamic nucleus, medial aspects of the nucleus accumbens and the medial and sulcal prefrontal cortices. Again, in each of these cases, labeling within any region of the hypothalamus could not be detected. Since MD stimulation activated the midline thalamus, and the nucleus reuniens in particular, the last phase of this experiment involved stimulation of the nucleus reuniens in order to determine the source of medial thalamic inputs to the hypothalamus. Stimulation of the nucleus reuniens activated fibers which were distributed to both the medial and lateral hypothalamus. In addition, stimulation also activated the descending periventricular system, which could be followed to the level of the midbrain central gray and such limbic structures as the hippocampal formation, septal area, amygdala and prefrontal cortex. These findings indicate that Pfc-MD activation of the hypothalamus is achieved indirectly via interneurons within the nucleus reuniens.

Animals↗
PubMed1988

Regulation of pathways of glucose metabolism in the kidney. The activity of the pentose phosphate pathway, glycolytic route and the regulation of phosphofructokinase in the kidney of lean and genetically obese (ob/ob) mice; comparison with effects of diabetes.

The activities of enzymes of the glycolytic route, the pentose phosphate pathway and NADPH-linked enzymes have been measured in the kidneys of genetically obese (ob/ob) mice and their lean litter mates. The renal content of glucose 6-phosphate (G6P), fructose 6-phosphate (F6P), fructose 1,6-bisphosphate (Fru-1,6-P2) and fructose 2,6-bisphosphate (Fru-2,6-P2) were also measured. Increases were found in hexokinase and enolase with an upward trend in pyruvate kinase in the ob/ob mouse kidney; a significant decline in malic enzyme was also seen. The renal content of G6P and Fru-1,6-P2 increased. There was no renal hypertrophy despite a degree of hyperglycaemia, which was, however, considerably below that observed in experimental diabetes. Comparison of the renal changes in the hyperglycaemic-hyperinsulinaemic ob/ob mice with the hyperglycaemic-hypoinsulinaemic diabetic group showed two distinct groupings. Firstly, changes which were similar in the two groups included: increases in hexokinase, G6P and Fru-1,6-P2, and a decrease in malic enzyme. Secondly, opposite changes were seen in enolase and in enzymes at the G6P crossroads, phosphoglucose isomerase and phosphoglucomutase. The elevated hexokinase and G6P in both ob/ob and diabetic groups may be involved in the eventual accumulation of basement membrane material in the glomerulus which is a common feature of the two conditions.

Animals↗
PubMed2004

Pathway-specific maturation, visual deprivation, and development of retinal pathway.

One of the fundamental features of the visual system is the segregation of neural circuits that process increments and decrements of luminance into ON and OFF pathways. In mature retina, the dendrites of retinal ganglion cells (RGCs) in the inner plexiform layer (IPL) of retina are separated into ON or OFF sublamina-specific stratification. At an early developmental stage, however, the dendrites of most RGCs are ramified throughout the IPL. The maturation of RGC ON/OFF dendritic stratification requires neural activities mediated by afferent inputs from bipolar and amacrine cells. The synchronized spontaneous burst activities in early postnatal developing retina regulate RGC dendritic filopodial movements and the maintenance or elimination of dendritic processes. After eye opening, visual experience further remodels and consolidates the retinal neural circuit into mature forms. Several neurotransmitter systems, including glutamatergic, acetylcholinergic, GABAergic, and glycinergic systems, might act together to modulate the RGC dendritic refinement. In addition, both the bipolar cells and cholinergic amacrine cells may provide laminar cues for the maturation of RGC dendritic stratification.

Animals↗
PubMed2001

Is the recovery of stepping following spinal cord injury mediated by modifying existing neural pathways or by generating new pathways? A perspective.

The recovery of stepping ability following a spinal cord injury may be achieved by restoring anatomical connectivity within the spinal cord. However, studies of locomotor recovery in animals with complete spinal cord transection suggest that the adult mammalian spinal cord can acquire the ability to generate stepping after all descending input is eliminated and in the absence of neuronal regeneration. Moreover, rehabilitative gait training has been shown to play a crucial role in teaching existing spinal pathways to generate locomotion and appropriately respond to sensory feedback. This brief review presents evidence that neural networks in the mammalian spinal cord can be modulated pharmacologically and/or with task-specific behavioral training to generate weight-bearing stepping after a spinal injury. Further, the role that spinal learning can play in the management of humans with spinal cord injury is discussed in relation to interventions that are designed primarily to enhance neuronal regeneration.

Animals↗
PubMed1981

The role of immunoglobulins in alternative complement pathway activation by zymosan. I. Human IgG with specificity for Zymosan enhances alternative pathway activation by zymosan.

Prior absorption of normal human serum (NHS) or C2-deficient human serum (C2D) with zymosan at 0 degrees C results in diminished consumption of C3 and factor B during subsequent incubation of the sera in Mg-EGTA buffer with zymosan at 37 degrees C for 30 min. An acid eluate from the zymosan restores the defect of absorbed NHS and C2D, and also enhances C3 and factor B utilization in hypogammaglobulinemic serum (H gamma S) in a dose-dependent fashion. The activity is specific in that the eluate from zymosan fails to enhance C3 and B depletion in H gamma S or absorbed NHS by lipopolysaccharide or Sepharose. The active component of th zymosan eluate emerges from both Sepharose 4B and Sephacryl S-200 in the region of molecules with m.w. of 150,000. Absorption with protein A-Sepharose removes the activity, demonstrating that it is IgG. Digestion of the IgG with pepsin fails to diminish activity, indicating that the Fc region is not required for activity; reduction to monovalent Fab' fragments, however, abrogates activity. When IgG antibody is bound to Protein A-Sepharose, it fails to enhance C3 depletion in H gamma S by Sepharose, indicating that binding of IgG antibody by the Fab region is necessary for enhancement of alternative pathway activity in human serum.

Antibody Specificity↗
PubMed1998

Cooperativity between the polyamine pathway and HER-2neu in transformation of human mammary epithelial cells in culture: role of the MAPK pathway.

Our experiments were designed to test the cooperativity between the polyamine pathway and HER-2neu in inducing transformation of human mammary epithelial cells in culture. Using the MCF-10A breast epithelial cell line, we observed that induction of overexpression of ornithine decarboxylase (ODC) (the first rate-limiting enzyme in polyamine biosynthesis) markedly potentiated the anchorage-independent growth stimulating effect of the beta2 isoform of neu differentiating factor (NDF) known to activate HER-2neu in MCF-10A cells. ODC overexpression, on the other hand, did not enhance growth in liquid culture, thus pointing to a specific effect on transformation rather than proliferation. ODC-overexpressing MCF-10A cells exhibited increased MAPK phosphorylation in response to administration of NDF and/or epidermal growth factor (EGF). In contrast, the phosphorylation of the members of the stress-activated protein kinase cascade p38 and SEK were not affected by ODC overexpression. Of note, in the absence of EGF and NDF, ODC overexpression failed to induce both clonogenicity and MAPK activation. These results suggest that increased polyamine biosynthetic activity critically interacts with HER-2neu in promoting human mammary cell transformation in culture and that the MAPK cascade is an important mediator of this interaction. If confirmed in future in vivo studies, our results may identify important new targets for the chemoprevention of human breast cancer.

Breast↗
PubMed2005

Curcumin-induced antiproliferative and proapoptotic effects in melanoma cells are associated with suppression of IkappaB kinase and nuclear factor kappaB activity and are independent of the B-Raf/mitogen-activated/extracellular signal-regulated protein kinase pathway and the Akt pathway.

BACKGROUND: Nuclear factor-kappaB (NF-kappaB) plays a central role in cell survival and proliferation in human melanoma; therefore, the authors explored the possibility of exploiting NF-kappaB for melanoma treatment by using curcumin, an agent with known, potent, NF-kappaB-inhibitory activity and little toxicity in humans. METHODS: Three melanoma cell lines (C32, G-361, and WM 266-4), all of which had B-raf mutations, were treated with curcumin, and the authors assessed its effects on viability ((3-[4,5-dimethylthiazol-2-yl]2,5-diphenyltetrazolium bromide assay) and apoptosis (flow-cytometric analysis of annexin V/propidium iodide-stained cells). Curcumin-treated cells also were examined for NF-kappaB binding activity (electrophoretic mobility shift assay) and for the activity of its upstream regulator, IkappaB kinase (IKK) (immune complex kinase assay). In addition, relevant signaling, as reflected by B-Raf kinase activity (kinase cascade assay), and steady-state levels of activated, downstream effectors, as reflected by mitogen-activated signal-regulated protein kinase (MEK), extracellular signal-regulated protein kinase (ERK), and Akt phosphorylation levels (immunoblots), were assessed. RESULTS: Curcumin treatment decreased cell viability of all 3 cell lines in a dose-dependent manner (50% inhibitory concentration = 6.1-7.7 microM) and induced apoptosis. NF-kappaB and IKK were active constitutively in all melanoma cell lines examined, and curcumin, under apoptosis-inducing conditions, down-regulated NF-kappaB and IKK activities. However, curcumin did not inhibit the activities of B-Raf, MEK, or ERK, and Akt phosphorylation was enhanced. Furthermore, in the presence of curcumin, the Akt inhibitor 1L-6-hydroxymethyl-chiro-inositol 2-[(R)-2-O-methyl-3-O-octadecylcarbonate] no longer suppressed Akt phosphorylation. CONCLUSIONS: Curcumin has potent antiproliferative and proapoptotic effects in melanoma cells. These effects were associated with the suppression of NF-kappaB and IKK activities but were independent of the B-Raf/MEK/ERK and Akt pathways.

Antineoplastic Agents↗
PubMed1983

Spatial relationships between the terminations of somatic sensory motor pathways in the rostral brainstem of cats and monkeys. II. Cerebellar projections compared with those of the ascending somatic sensory pathways in lateral diencephalon.

Previous studies have shown that ascending somatic sensory pathways arising from the dorsal column nuclei, lateral cervical nucleus and spinothalamic tract terminate in parts of the thalamus adjacent to those which receive cerebellar terminations. This termination pattern creates a border between the ventroposterolateral nucleus (VPL) and the ventrolateral nucleus (VL) in the cat and between the caudal and oral parts of VPL (VPLc and VPLo, respectively) in the monkey. Since it is not clear how sharp these borders are, a double orthograde labeling strategy was used in the present study to make direct comparisons of the projections to the thalamus from these sources of input. It was found that there was a change in the sources of afferent input to the different target areas that paralleled changes in cytoarchitecture. Moving caudally to rostrally, VPL in the cat and VPLc in the monkey received projections predominantly from the middle, dorsal (clusters) portion of the dorsal column nuclei. These projections were gradually replaced near the VPL-VL border in the cat and VPLc-VPLo border in the monkey first by input from the lateral cervical nucleus (cat only) and the rostral and ventral portions of the dorsal column nuclei and then by spinothalamic projections. Towards VL in the cat and the rostral parts of VPLo in the monkey (referred to as Vim by Hassler, '59 and Mehler, '71), these projections were in turn replaced by those from the cerebellum. This sequence resulted in a complex pattern (summarized in Fig. 10) where some thalamic territories received input predominantly from one source and others received converging input from several sources. The major region receiving converging ascending somatic sensory and cerebellar terminations was located at the border between VPL and VL in the cat and in the caudal parts of Olszewski's ('52) VPLo in the monkey (that is, between VPLc and Vim). In general, the results in the cat were similar to those in the monkey. One notable difference was that the domain containing terminals from the cerebellum and the rostral-ventral parts of the dorsal column nuclei was located medially between VPLc and Vim in the monkey, whereas it extended across the entire mediolateral border between VPL and VL in the cat. In both species, thalamic neurons received input predominantly from one afferent source and only minor input, if any, from other sources.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗
PubMed1989

Primate spinothalamic pathways: II. The cells of origin of the dorsolateral and ventral spinothalamic pathways.

The cells of origin of the dorsolateral (DSTT) and the ventral (VSTT) spinothalamic tracts were studied in 11 monkeys. The spinothalamic tract cells were retrogradely labeled by horseradish peroxidase (HRP) injected in the thalamus. All animals also received a midthoracic spinal cord lesion on the side ipsilateral to the thalamic injections. The distribution of labeled cells found in these animals throughout the cervical segments was similar to animals with no spinal cord lesions. Five animals had ventral quadrant lesions to demonstrate the cells of origin of the DSTT. In macaques with complete ventral quadrant lesions, more than 80% of the HRP label in the contralateral L4-L7 segments was located in lamina I, while in squirrel monkeys, the label in the contralateral lower lumbar region was distributed between laminae I-III and IV-VI. Few labeled cells were found in laminae VII-X. Six animals received dorsolateral funiculus lesions to demonstrate the cells of origin of the VSTT. In animals with adequate lesions, 84-99% of the contralateral HRP label in L4-L7 was located in laminae IV-X. Macaques had a larger percentage of labeled cells located in lamina I than squirrel monkeys. The results indicate the existence of two spinothalamic pathways in the primate. The DSTT was calculated to compose about one fourth of the total spinothalamic population.

Animals↗
PubMed1989

Primate spinothalamic pathways: III. Thalamic terminations of the dorsolateral and ventral spinothalamic pathways.

The termination sites of the dorsolateral (DSTT) and ventral (VSTT) spinothalamic pathways were determined by using anterograde transport of horseradish peroxidase from the lumbar spinal cord in primates. One animal had no spinal cord lesion, while of two other animals, one received a midthoracic dorsolateral funiculus lesion, and the other received a midthoracic ventral quadrant lesion contralateral to the injection. The thalamic label in the animal with no spinal cord lesion was much less than the label in the two animals with spinal lesions. Moreover, in the animals with spinal lesions, HRP-labeled cells were found within the thalamus. Therefore, the remaining six animals received ipsilateral hemisections and bilateral dorsal column lesions, irrespective of the contralateral lesions. The thalamic label in the animals without contralateral lesions were assumed to represent the total spinothalamic input to the diencephalon. In these animals, label was located mainly in suprageniculate and pulvinar oralis, caudal and oral divisions of ventral posterior lateral nucleus, the lateral half of ventral posterior inferior nucleus, and zona incerta, while in the medial thalamus label was primarily in two distinct bands in medial dorsal nucleus and in the posterior dorsal portion of central lateral nucleus. Scattered lighter labeling was found in other thalamic nuclei. The pattern of terminal labeling observed in the ventral posterior lateral region was arranged in patches, while elsewhere in the thalamus a more uniform labeling pattern was observed. The thalamic label in animals with contralateral ventral quadrant lesions represented the terminations of the DSTT, while the label in animals with contralateral dorsolateral funiculus lesions represented VSTT terminations. The labeling pattern was similar between these two groups. However, there were small differences between them. These results indicate that DSTT and VSTT terminations largely overlap and innervate the lateral and medial thalamamus.

Animals↗
PubMed1999

A unique reaction in a common pathway: mechanism and function of chorismate synthase in the shikimate pathway.

Chorismate synthase, the seventh enzyme in the shikimate pathway, catalyzes the transformation of 5-enolpyruvylshikimate 3-phosphate to chorismate which is the last common precursor in the biosynthesis of numerous aromatic compounds in bacteria, fungi and plants. The enzyme has an absolute requirement for reduced FMN as a cofactor, although the 1,4-anti elimination of phosphate and the C(6proR)-hydrogen does not involve a net redox change. The role of the reduced FMN in catalysis has long been elusive. However, recent detailed kinetic and bioorganic approaches have fundamentally advanced our understanding of the mechanism of action, suggesting an initial electron transfer from tightly bound reduced flavin to the substrate, a process which results in C-O bond cleavage. Studies on chorismate synthases from bacteria, fungi and plants revealed that in these organisms the reduced FMN cofactor is made available in different ways to chorismate synthase: chorismate synthases in fungi--in contrast to those in bacteria and plants--carry a second enzymatic activity which enables them to reduce FMN at the expense of NADPH. Yet, as shown by the analysis of the corresponding genes, all chorismate synthases are derived from a common ancestor. However, several issues revolving around the origin of reduced FMN, as well as the possible regulation of the enzyme activity by means of the availability of reduced FMN, remain poorly understood. This review summarizes recent developments in the biochemical and genetic arena and identifies future aims in this field.

Catalysis↗
PubMed1984

Regulation of alternative pathways of glucose metabolism in rat heart in alloxan diabetes: changes in the pentose phosphate pathway.

The flux of glucose through the pentose phosphate pathway, important in relation to the provision of ribose 5-phosphate for nucleotide and RNA synthesis, was decreased by 70% in the diabetic rat heart in parallel with a similar decreased flux through the glycolytic route. A common factor linking the decreased flux through these alternative routes is the known fall in cardiac hexokinase; in these experiments there is a 50% decrease in Type II hexokinase (EC 2.7.1.1.) in both soluble and particulate fractions. The level of fructose 2,6-bisphosphate, a regulator of phosphofructokinase activity, is decreased by 20% in the alloxan diabetic rat heart, this may be a significant additional factor in the marked decrease in the flux of glucose through the glycolytic route in the myocardium in diabetes.

Animals↗
PubMed1986

Do rat hepatic microsomes contain multiple NADPH-supported fatty acid chain elongation pathways or a single pathway?

[2-14C]-trans-2-hexadecenoyl CoA (16:1) and [2-14C]-trans-2-cis-8,11,14-eicosatetraenoyl CoA (20:4) were chemically synthesized and employed as competitive substrates for the liver microsomal trans-2-enoyl CoA reductase component of the fatty acid chain elongation system. Both 7.5 microM and 15 microM 20:4 competitively inhibited the reduction of 16:1 CoA to palmitoyl CoA. In addition, the reduction of both substrates was identically inhibited to the same extent by the acetylenic derivative, dec-2-ynoyl CoA. Furthermore, trypsin, chymotrypsin and subtilisin inhibited trans-2-enoyl CoA reductase activity when three different substrates were employed--16:1, 20:4 and trans-2-cis-11-octadecadienoyl CoA (18:2). These results are consistent with the hypothesis of multiple condensing enzymes connected to a single elongation pathway.

Acyl-CoA Dehydrogenases↗
PubMed1983

Embryogenesis of peripheral nerve pathways in grasshopper legs. I. The initial nerve pathway to the CNS.

The founding of the first nerve path of the grasshopper metathoracic leg was examined at the level of identified neurons, using intracellular dye fills, immunohistochemistry, Nomarski optics, and scanning and transmission electron microscopy. The embryonic nerve is established by the axonal trajectory of a pair of afferent pioneer neurons, the tibial 1 (Ti1) cells. Following a period of profuse filopodial sprouting, the Ti1 axonal growth cones, possessing 75- to 100-microns-long filopodia, navigate a stereotyped path across the limb bud epithelium to the base of the appendage and into the CNS. The Ti1 axons grow from cell to cell along a chain of preaxonogenesis neurons spaced at intervals along the pathway, forming dye-passing junctions with them. The contacted neurons subsequently undergo axonogenesis and follow the pioneer axons into the CNS. Later arising neurons project their axons onto the cell bodies of the chain, thereby establishing the principal branch points of the nerve. Among the later arising afferents are the sensory neurons of the femoral chordotonal and subgenual organs. The morphology of the adult nerve appears to be determined by the stereotyped positioning of neurons in the differentiating limb bud and by the resultant axonal trajectories established during the first 10% of peripheral neurogenesis.

Animals↗
PubMed1991

Ultracytochemistry of the secretory pathway in Saccharomyces cerevisiae defies the established pathway model.

The molecular and cell biologic data supporting the established model of the intracellular secretory (transport) pathway for glycoproteins in the yeast Saccharomyces cerevisiae have been reviewed and confronted with our electron-cytochemical findings. These in situ findings show a new class of constitutive intracellular conveyors--the coated globules--and also suggest substantial alternatives in the cellular mechanism of the vacuole biogenesis. The controversial question of the Golgi compartment identity in S. cerevisiae is revived.

Dipeptidyl-Peptidases and Tripeptidyl-Peptidases↗
PubMed2005

High glucose-induced apoptosis in human vascular endothelial cells is mediated through NF-kappaB and c-Jun NH2-terminal kinase pathway and prevented by PI3K/Akt/eNOS pathway.

Our previous studies demonstrated that high glucose-induced apoptosis in human umbilical vein endothelial cells (HUVECs) is mediated by sequential activation of c-Jun N-terminal kinase (JNK) and caspase, and prevented by exogenous nitric oxide (NO). In this study we further elucidated the roles of the transcriptional factor NF-kappaB, phosphatidylinositol 3'-kinase (PI3K), Akt and endothelial nitric oxide synthase (eNOS) in the apoptosis of HUVECs induced by high glucose. The results showed that high glucose-induced apoptosis was significantly enhanced by PI3K inhibitors (wortmannin and LY294002), NOS inhibitor (NG-nitro-arginine methyl ester) and eNOS antisense oligonucleotide. In contrast, apoptosis was markedly reduced by NF-kappaB inhibitor (pyrrolidine dithiocarbamate, PDTC), NF-kappaB antisense oligonucleotide, NO donor (sodium nitroprusside, SNP), and overexpression of Akt. The high glucose-induced NF-kappaB activation and transient Akt phosphorylation were prevented by the presence of vitamin C. Moreover, high glucose-induced increase in eNOS expression was attenuated by PI3K inhibitors and the negative mutant of PI3K. The activity of JNK induced by high glucose was suppressed by NF-kappaB-specific antisense oligonucleotide. Taken together our results demonstrated that high glucose-induced HUVECs apoptosis is through NF-kappaB-dependent JNK activation and reactive oxygen species (ROS)-dependent Akt dephosphorylation. Activation of the ROS/PI3K/Akt/eNOS signaling pathway in early phase exerts protective effects against the induction of apoptosis by high glucose.

Androstadienes↗
PubMed2004

Engineering biosynthetic pathways for deoxysugars: branched-chain sugar pathways and derivatives from the antitumor tetracenomycin.

Sugar biosynthesis cassette genes have been used to construct plasmids directing the biosynthesis of branched-chain deoxysugars: pFL942 (NDP-L-mycarose), pFL947 (NDP-4-deacetyl-L-chromose B), and pFL946/pFL954 (NDP-2,3,4-tridemethyl-L-nogalose). Expression of pFL942 and pFL947 in S. lividans 16F4, which harbors genes for elloramycinone biosynthesis and the flexible ElmGT glycosyltransferase of the elloramycin biosynthetic pathway, led to the formation of two compounds: 8-alpha-L-mycarosyl-elloramycinone and 8-demethyl-8-(4-deacetyl)-alpha-L-chromosyl-tetracenomycin C, respectively. Expression of pFL946 or pFL954 failed to produce detectable amounts of a novel glycosylated tetracenomycin derivative. Formation of these two compounds represents examples of the sugar cosubstrate flexibility of the ElmGT glycosyltransferase. The use of these cassette plasmids also provided insights into the substrate flexibility of deoxysugar biosynthesis enzymes as the C-methyltransferases EryBIII and MtmC, the epimerases OleL and EryBVII, and the 4-ketoreductases EryBIV and OleU.

Antineoplastic Agents↗
PubMed2000

Xenopus Xenf: an early endodermal nuclear factor that is regulated in a pathway distinct from Sox17 and Mix-related gene pathways.

We report a novel zygotic gene encoding a Xenopus endodermal nuclear factor, Xenf. Expression of Xenf starts at the late blastula stages and is decreased after gastrulation. Xenf shows no structural homology to any known proteins. When GFP-tagged Xenf is overexpressed in Xenopus cells, Xenf protein is localized to the nucleus, associating closely with the chromosomes. In animal cap assays, Xenf expression is strongly activated by mRNA injection of Vg1 and VegT, maternal vegetal genes that can induce endodermal differentiation. In contrast, Xenf is not induced by endoderm-inducing zygotic transcription factors such as Sox17 and Mix-related genes. In turn, Xenf does not activate expression of Sox17, Mixer or Milk. Thus, Xenf is regulated by maternal vegetal positional information in a parallel manner to Sox17 and Mix-related gene pathways.

Amino Acid Sequence↗