Increased Binding of Epidermal Growth Factor at Preimplantation Sites in Mouse Uteri

Brown, M.; J, Zogg; Schultz, Gregory S.; Hilton, Frederick K.

doi:10.1210/endo-124-6-2882

Cited by 40 publications

(9 citation statements)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We did not examine [ 25 I]-EGF binding throughout the length of the uterine horns. Therefore we cannot rule out the possibility that regional differences in binding similar to those reported to occur between implantation and interimplantation sites in mice [54] might be responsible for the dissimilar amounts of EGF-R mRNA recovered from skunk uteri during delayed implantation and the period of renewed embryonic development. However, the latter data were obtained by extracting mRNA from entire uteri collected before blastocyst implantation; half of these specimens contained blastocysts measuring between 1.2 and 1.6 mm in diameter and were classified as early-activation specimens (i.e., collected before blastocyst spacing).…”

Section: Discussionmentioning

confidence: 88%

Expression of Epidermal Growth Factor Receptor in the Preimplantation Uterus and Blastocyst of the Western Spotted Skunk1

Paria

Das²,

Mead³

et al. 1994

Biology of Reproduction

View full text Add to dashboard Cite

The western spotted skunk is unique in that its blastocysts undergo a 180-220-day period of arrested development before implantation. We investigated the potential role of epidermal growth factor (EGF)-related growth factors in regulating uterine and embryonic development in this species by studying the status of EGF receptor (EGF-R) in these tissues during delayed implantation and resumption of embryonic development. The cell-specific distribution of EGF binding sites and the expression of EGF-R mRNA were assayed by autoradiography and Northern blot analysis, respectively. The size of EGF-R was determined by affinity cross-linking studies, and its bioactivity was examined by determining EGF-dependent subcellular protein tyrosine kinase (PTK) activity. EGF binding sites were localized in the uterine luminal and glandular epithelium, endometrial stroma, myometrium, and blood vessels during both stages of pregnancy. As examined by Northern blot hybridization, a cRNA probe specific to mouse EGF-R hybridized to poly(A)+ RNA of skunk uteri. Transcripts similar to those of mouse uterine EGF-R were identified. [125I]-EGF was cross-linked to a 170-kDa protein both in the uterus and in blastocysts collected during the delayed implantation and periimplantation periods. However, EGF-induced PTK activity was significantly elevated above background levels during the period of renewed embryonic development, but not during arrested embryonic development. The results suggest that EGF-related growth factors may play an important role in regulating embryonic development in this species and that a change in the number and/or functional status of the EGF-R may be a prerequisite for blastocyst activation and implantation in the spotted skunk.

show abstract

Section: Discussionmentioning

confidence: 88%

Expression of Epidermal Growth Factor Receptor in the Preimplantation Uterus and Blastocyst of the Western Spotted Skunk1

Paria

Das²,

Mead³

et al. 1994

Biology of Reproduction

View full text Add to dashboard Cite

show abstract

“…For implantation mouse embryos distribute along the length of the two uterine horns, associated with regionalized expression of epidermal growth factor (EGF) receptors in the uterus (Brown et al 1989;Das et al 1994). Physical contact initiates a localized decidual response in the uterus, and the embryo becomes directionally embedded in the deciduum.…”

Section: Egg Cylinder Development and Episcsmentioning

confidence: 99%

Pluripotency in the Embryo and in Culture

Nichols

Smith

2012

Cold Spring Harbor Perspectives in Biology

272

254

View full text Add to dashboard Cite

SUMMARYSpecific cells within the early mammalian embryo have the capacity to generate all somatic lineages plus the germline. This property of pluripotency is confined to the epiblast, a transient tissue that persists for only a few days. In vitro, however, pluripotency can be maintained indefinitely through derivation of stem cell lines. Pluripotent stem cells established from the newly formed epiblast are known as embryonic stem cells (ESCs), whereas those generated from later stages are called postimplantation epiblast stem cells (EpiSCs). These different classes of pluripotent stem cell have distinct culture requirements and gene expression programs, likely reflecting the dynamic development of the epiblast in the embryo. In this chapter we review current understanding of how the epiblast forms and relate this to the properties of derivative stem cells. We discuss whether ESCs and EpiSCs are true counterparts of different phases of epiblast development or are culture-generated phenomena. We also consider the proposition that early epiblast cells and ESCs may represent a naïve ground state without any prespecification of lineage choice, whereas later epiblasts and EpiSCs may be primed in favor of particular fates.

show abstract

“…In day 5 dormant blastocysts, EGF-R mRNA levels per cell were reduced "8-fold relative to those in normal day 4 blastocysts. EGF-R mRNA levels remained low in dormant day 7 blastocysts, but 8 h after E2 injection EGF-R mRNA copies per cell in the activated day 7 blastocysts had increased '4-fold (Table 1). These results suggest that the steady-state levels of EGF-R mRNA are in relatively low abundance in the cells of the blastocyst.…”

mentioning

confidence: 99%

“…Expression of several polypeptide growth factors and their receptors in the uterus (4)(5)(6)(7)(8) and embryo (9)(10)(11)(12)(13)(14)(15)(16) suggests their involvement in ovarian steroid effects on preimplantation embryo development and implantation. Recent studies document that the blastocyst has epidermal growth factor receptors (EGF-Rs) (11,12,15) and that EGF or transforming growth factor a (TGF-a) has beneficial effects on preimplantation embryo development (11,12).…”

mentioning

confidence: 99%

Expression of the epidermal growth factor receptor gene is regulated in mouse blastocysts during delayed implantation.

Paria

Das

Andrews

et al. 1993

Proc. Natl. Acad. Sci. U.S.A.

176

View full text Add to dashboard Cite

The delayed implantation model was used to study epidermal growth factor receptor(s) (EGF-R) in the mouse blastocyst. Delayed implantation and blastocyst dormancy were induced by ovariectomy on day 4 of pregnancy and were maintained by daily (days 5-7) injections of progesterone (P4). Blastocyst activation and implantation were initiated by coinjection ofestradiol-178 (E2) with P4 on the 3rd day ofdelay. Immunostaining of EGF-R, autoradiographic detection of 12SI-labeled EGF binding, and measurement of EGF-inducible subcellular protein tyrosine phosphorylation demonstrated the loss of EGF-R from blastocysts (dormant) recovered 24 h after ovariectomy or on the 3rd day of P4-maintained delay. However, increased EGF-R levels were detected in blastocysts (activated) recovered 12 or 24 h after E2 injection. Blastocyst EGF-R mRNA levels were quantitated by reverse transcriptase (RT)-PCR and distribution of this mRNA was examined by in situ hybridization. To provide a homologous probe for these studies, a mouse EGF-R partial cDNA was cloned and used as the template for synthesis of antisense-and sense-strand EGF-R RNA. Quantitative RT-PCR demonstrated an 8-to 10-fold reduction in EGF-R mRNA copies per cell in dormant blastocysts. In contrast, an 8-fold increase in EGF-R mRNA copies per cell was detected in activated blastocysts 8 h after injection of E2. In situ hybridization detected EGF-R mRNA in most cells of normal day 4 blastocysts but not in those of dormant blastocysts. These studies establish that expression of the EGF-R gene in mouse blastocysts is tightly regulated by maternal steroid hormonal status.Successful implantation requires synchrony between embryo development and establishment of the receptive state of the uterus (1). These processes are primarily regulated by ovarian estrogen and progesterone (P4). In the mouse, ovariectomy before the presumed estrogen surge in the morning of day 4 results in implantation failure and initiates a state of blastocyst dormancy (2, 3), a condition referred to as delayed implantation. Delayed implantation can be maintained for several days by continued P4 treatment. However, blastocyst activation and implantation can be rapidly initiated by an injection of estrogen (2, 3). Mechanisms by which estrogen regulates the processes of blastocyst activation and implantation are poorly understood.Expression of several polypeptide growth factors and their receptors in the uterus (4-8) and embryo (9-16) suggests their involvement in ovarian steroid effects on preimplantation embryo development and implantation. Recent studies document that the blastocyst has epidermal growth factor receptors (EGF-Rs) (11,12,15) and that EGF or transforming growth factor a (TGF-a) has beneficial effects on preimplantation embryo development (11,12). The presence of TGF-a in the uterine luminal epithelium before implantation (5) further suggests that TGF-a plays a role in implantation.Effects of TGF-a or EGF are mediated by binding to the EGF-R (17). The EGF-R is a 170-kDa transmembrane prot...

show abstract

Increased Binding of Epidermal Growth Factor at Preimplantation Sites in Mouse Uteri

Cited by 40 publications

References 24 publications

Expression of Epidermal Growth Factor Receptor in the Preimplantation Uterus and Blastocyst of the Western Spotted Skunk1

Expression of Epidermal Growth Factor Receptor in the Preimplantation Uterus and Blastocyst of the Western Spotted Skunk1

Pluripotency in the Embryo and in Culture

Expression of the epidermal growth factor receptor gene is regulated in mouse blastocysts during delayed implantation.

Contact Info

Product

Resources

About