Embryogenesis requires the precise movement and reorganization of many cell and tissue types. Presumably, cell surface receptors allow cells to interact selectively with adjacent cells and with the extracellular environment, as well as initiate differentiative events by transducing appropriate signals across the plasma membrane. One cell surface component that serves as a receptor during a variety of cellular interactions is β1,4‐galactosyltransferase. Cell surface galactosyltransferase participates in diverse cellular interactions by binding its specific glycoconjugate substrate on adjacent cell surfaces or in (...) the extracellular matrix. Biochemical, immunological, and molecular probes are being used to better define cell surface galactosyl‐transferase functional in cellular interactions during fertilization, intercellular adhesion, cell migration, and growth control. (shrink)

Abstractβ1,4‐galactosyltransferase is unusual among the glycosyltransferases in that it is found in two subcellular compartments where it performs two distinct functions. In the trans‐Golgi complex, galactosyltransferase participates in oligosaccharide biosynthesis, as do the other glycosyltransferases. On the cell surface, however, galactosyltransferase associates with the cytoskeleton and functions as a receptor for extracellular oligosaccharide ligands. Although we now know much regarding galactosyltransferase function in these two compartments, little is known about how it is targeted to these different sites. By cloning the (...) galactosyltransferase gene products, certain features of the protein have been identified that may be critical for its expression on the cell surface or retention within the Golgi complex. This article discusses recent studies which suggest that a cytoplasmic sequence unique to one galactosyltransferase isoform is required for targeting a portion of this protein to the plasma membrane, enabling it to function as a cell adhesion molecule. These findings allow one to manipulate surface galactosyltransferase expression, either positively or negatively, and perturb galactosyltransferase‐dependent cellular interactions during fertilization and development. (shrink)

[1] Nisayon le-hadrikh et ben-dorenu bi-khenisato le-tokh ʻolam ha-Torah uvi-shelabe ʻaliyato -- ḥeleḳ 2. Nisayon le-hadrikh et ben dorenu bi-khenisato la-ʻavodah musarit.

Mike Shur’s Netflix-aired The Good Place has been a focus of philosophical attention by both popular-culture (written by pop-philosophers) and professional philosophers. This attention is merited. The Good Place is a philosophically rich TV show. The Good Place is based in three places: The Good Place, The Medium Place and The Bad Place. Every human being ends up in one of these places after they die based on their good points (points received for doing good actions e.g., chewing with your (...) mouth closed) and bad points (points received for doing bad actions e.g., virtue-signaling). Spoiler alert: by Season 4 of The Good Place (the fourth and final season), the main characters of the show – Eleanor, Chidi, Jason and Tahani – eventually reach the real Good Place (not the fake “Good Place” they had been tortured in by the human-formed, architect demon Michael in Season 1). However, when they reach the real Good Place after much struggle with ethical dilemmas, recognition of their moral flaws and moral development, they find themselves wanting to leave: they were unsatisfied with what The Good Place had to offer and wanted to be freed from it. This paper is concerned with the following questions: What accounts for their desire to be freed from The Good Place? What kind of freedom were they trying to achieve, and how did The Good Place represent it? Reflecting on these (and similar) questions, I argue that St. Thomas (who made it into The Good Place!) gives an ingenious and plausible answer: it was not merely that The Good Place was characterized by pure hedonism (a core deficit of The Good Place, identified by its creators), but more specifically that they had a positive desire for a freedom from temporal goods/experiences which do not satisfy the longings of the human heart and a freedom for the enjoyment of perfect freedom. While The Good Place ends in much perplexity, I argue that the freedom they desired was a rudimentary articulation of the freedom that St. Thomas identifies in heaven. (shrink)