Related Experiment Video
Updated: Feb 25, 2026
05:13
Author Spotlight: Advancing Therapeutic Strategies for Improving Pregnancy Rates by Analyzing Embryo-Endometrium Interactions
Published on: June 21, 2024
1.7K
Embryo implantation evolved from an ancestral inflammatory attachment reaction
Oliver W Griffith1,2, Arun R Chavan3,2, Stella Protopapas3,2
1Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT 06520; oliver.griffith@yale.edu.
Summary
Marsupial pregnancy shares molecular similarities with eutherian implantation, particularly an inflammatory response. This suggests conserved attachment mechanisms evolved from an ancestral therian mammal.
Area of Science:
- Reproductive Biology
- Developmental Biology
- Comparative Genomics
Background:
- Eutherian implantation involves complex molecular changes to establish pregnancy.
- Marsupial pregnancy is short, with a transient placenta and uterine changes mimicking implantation at term.
Purpose of the Study:
- To investigate molecular similarities between marsupial term pregnancy and eutherian implantation.
- To use the gray short-tailed opossum (Monodelphis domestica) as a model for comparative analysis.
Main Methods:
- Transcriptomic analysis of the opossum uterus at term.
- Immunohistochemistry to examine materno-fetal interface.
- Comparison of gene expression profiles with eutherian implantation data.
Main Results:
- Opossum term pregnancy exhibits an inflammatory response similar to eutherian implantation.
- Key implantation markers (Heparin binding EGF-like growth factor, Mucin 1) show conserved expression.
- Transcriptome-wide similarities exist between opossum attachment and eutherian implantation.
Conclusions:
- The eutherian implantation reaction likely evolved from an ancestral therian attachment reaction.
- Marsupials retain this attachment reaction, leading directly to parturition.
- The evolution of a non-inflammatory pregnancy phase was crucial for extended eutherian placentation.
Related Concept Videos
01:33Cleavage and Blastulation
50.7K
After a large-single-celled zygote is produced via fertilization, the process of cleavage occurs while zygotes travel through the uterine tube. Cleavage is a mitotic cell division that does not result in growth. With each round of successive cell division, daughter cells get increasingly smaller.
50.7K
01:10Zygotic Development And Stem Cell Formation
7.0K
The development of all multicellular organisms starts with the fusion of haploid cells called sperm and egg to form a diploid zygote. A zygote is a totipotent cell that can develop into a complete organism. The zygote undergoes cell division or cleavage to form an 8-cell mass. Until this stage, the cells are spherical, loosely attached, and remain totipotent. Totipotent cells are capable of developing both the embryonic and the extraembryonic tissues. However, as they continue to divide, they...
7.0K
01:56Gastrulation
68.0K
Gastrulation establishes the three primary tissues of an embryo: the ectoderm, mesoderm, and endoderm. This developmental process relies on a series of intricate cellular movements, which in humans transforms a flat, “bilaminar disc” composed of two cell sheets into a three-tiered structure. In the resulting embryo, the endoderm serves as the bottom layer, and stacked directly above it is the intermediate mesoderm, and then the uppermost ectoderm. Respectively, these tissue strata...
68.0K
01:20Embryonic Connective Tissues
7.0K
During early development, the embryo forms two types of connective tissues— the mesenchyme and mucoid connective tissue.
The mesenchyme is the first connective tissue that emerges in the developing embryo. It consists of loosely arranged multipotent mesenchymal cells and reticular fibers in the extracellular matrix. This loose arrangement allows easy migration of cells, which is essential for germ layer positioning, patterning, and organ morphogenesis during embryonic development.
The mesenchyme is the first connective tissue that emerges in the developing embryo. It consists of loosely arranged multipotent mesenchymal cells and reticular fibers in the extracellular matrix. This loose arrangement allows easy migration of cells, which is essential for germ layer positioning, patterning, and organ morphogenesis during embryonic development.
7.0K
01:30Neurulation
46.6K
Neurulation is the embryological process which forms the precursors of the central nervous system and occurs after gastrulation has established the three primary cell layers of the embryo: ectoderm, mesoderm, and endoderm. In humans, the majority of this system is formed via primary neurulation, in which the central portion of the ectoderm—originally appearing as a flat sheet of cells—folds upwards and inwards, sealing off to form a hollow neural tube. As development proceeds, the...
46.6K
01:38Fertilization
92.3K
During fertilization, an egg and sperm cell fuse to create a new diploid structure. In humans, the process occurs once the egg has been released from the ovary, and travels into the fallopian tubes. The process requires several key steps: 1) sperm present in the genital tract must locate the egg; 2) once there, sperm need to release enzymes to help them burrow through the protective zona pellucida of the egg; and 3) the membranes of a single sperm cell and egg must fuse, with the sperm...
92.3K