The idea that glycosphingolipids (or, briefly, glycolipids) are ubiquitous components of plasma membrane and display cell type-specific patterns perhaps stemmed from the classical studies on glycolipids of erythrocyte membranes.(1,2) Subsequently, plasma membranes of various animal cells were successfully isolated and analyzed; all were characterized by their much higher content of glycolipid than was found in intracellular membranes.(3–8) It is generally assumed that glycolipids are present at the outer leaflet of the plasma membrane bilayer, although this assumption is based only on experiments with surface-labeling by galactose oxidase-NaB[3H]4 of intact and lysed erythrocyte membranes and inside-out vesicles.(9,10) Obviously, further extensive studies of the organization of glycolipid in other eukaryotic cell membranes are necessary. Interestingly, the majority of neutral glycolipids present in plasma membranes are cryptic (see Section 4.2.1).

Glycosphingolipids in Cellular Interaction, Differentiation, and Oncogenesis

A monoclonal antibody derived by fusion of mouse myeloma cells with spleen cells from a mouse immunized with F9 teratocarcinoma cells is described. This antibody, which reacts with embryonal carcinoma cells of mouse and human origin and with some preimplantation stage mouse embryos, defines an embryonic stage-specific antigen. This stage-specific antigen (SSEA-1) is first detected on blastomeres of 8-cell stage embryos. Trophectodermal cells are transitorily positive; however, each cell in the inner cell mass eventually expresses this antigen.

https://www.pnas.org/content/pnas/75/11/5565.full.pdf

Monoclonal antibody defining a stage-specific mouse embryonic antigen (SSEA-1).

There is growing interest in the possibility that genetic compatibility may drive mate choice, including gamete choice, particularly from the perspective of understanding why females frequently mate with more than one male. Mate choice for compatibility differs from other forms of choice for genetic benefits (such as ‘good genes’) because individuals are expected to differ in their mate preferences, changing the evolutionary dynamics of sexual selection. Recent experiments designed to investigate genetic benefits of polyandry suggest that mate choice on the basis of genetic compatibility may be widespread. However, in most systems the mechanisms responsible for variation in compatibility are unknown. We review potential sources of variation in genetic compatibility and whether there is any evidence for mate choice driven by these factors. Selfish genetic elements appear to have the potential to drive mate compatibility mate choice, though as yet there is only one convincing example. There is abundant evidence for assortative mating between populations in hybrid zones, but very few examples where this is clearly a result of selection against mating with genetically less compatible individuals. There are also numerous cases of inbreeding avoidance, but little evidence that mate choice or differential fertilization success driven by genetic compatibility occurs between unrelated individuals. The exceptions to this are a handful of situations where both the alleles causing incompatibility and the alleles involved in mate choice are located in a chromosome region where recombination is suppressed. As yet there are only a few potential sources of genetic compatibility which have clearly been shown to drive mate choice. This may reflect limitations in the potential for the evolution of mate choice for genetic compatibility within populations, although the most promising sources of such incompatibilities have received relatively little research.

http://www.selfishgene.org/Tom/Papers/TTNW_MolEcol00.pdf

Genetic compatibility, mate choice and patterns of parentage: invited review.

In the last decade there has emerged an appreciation of the remarkable similarity between the cells that give rise to teratocarcinomas in mice and the cells that give rise to the developing mouse embryo. The resemblance is so close that in certain instances the tumor stem cells can join with their embryonic counterparts and develop into a completely normal mouse. The availability of stem cell lines isolated from mouse teratocarcinomas has made possible a number of new biochemical, immunological, and genetic approahes to the study of early mammalian development.

https://science.sciencemag.org/content/sci/209/4458/768.full.pdf

Teratocarcinomas and mammalian embryogenesis

Monoclonal antibodies for analysis of the HLA system.

Syngeneic antisera have been produced in mouse strain 129/Sv-CP males against the primitive cells of teratocarcinoma. These sera react specifically with the primitive cells and are negative on various types of differentiated teratoma cells derived from the same original tumor. They are negative on all other mouse cells tested, with the exception of male germ cells and cleavage-stage embryos. Thus, teratoma cells possess cell-surface antigens in common with normal cleavage-stage embryos.

Surface Antigens Common to Mouse Cleavage Embryos and Primitive Teratocarcinoma Cells in Culture

Gene mapping within the T/t complex of the mouse. II. Anomalous position of the H-2 complex in t haplotypes

A major testicular cell protein specified by a mouse T/t complex gene

Letter: Absence of serologically detectable H-2 on primitive teratocarcinoma cells in culture.

A cell-surface antigen common to mouse primitive teratocarcinoma cells, morulae, and sperm has been shown by serological methods to be specified by a wild-type T-locus gene whose mutant form is lethal in homozygotes at the morula stage.

Karen Artzt

Papers

Surface Antigens Common to Mouse Cleavage Embryos and Primitive Teratocarcinoma Cells in Culture

Gene mapping within the T/t complex of the mouse. II. Anomalous position of the H-2 complex in t haplotypes

A major testicular cell protein specified by a mouse T/t complex gene

Letter: Absence of serologically detectable H-2 on primitive teratocarcinoma cells in culture.

Primitive Teratocarcinoma Cells Express a Differentiation Antigen Specified by a Gene at the T-Locus in the Mouse