ADP-ribosylation factor-like GTPase ARFRP1 is required for trans-Golgi to plasma membrane trafficking of E-cadherin.

ADP-ribosylation factor-related protein 1 (ARFRP1) plays a specific role in Golgi function controlling recruitment of GRIP domain proteins and ARL1 to the trans-Golgi. Deletion of the mouse Arfrp1 gene causes embryonic lethality during early gastrulation, because epiblast cells detach from the ectodermal cell layer and do not differentiate to mesodermal tissue. Here we show that in Arfrp1(-/-) embryos E-cadherin is mistargeted to intracellular compartments, whereas in control embryos it is present at the cell surface of trophectodermal and ectodermal cells.

Targeted disruption of Slc2a8 (GLUT8) reduces motility and mitochondrial potential of spermatozoa.

GLUT8 is a class 3 sugar transport facilitator which is predominantly expressed in testis and also detected in brain, heart, skeletal muscle, adipose tissue, adrenal gland, and liver. Since its physiological function in these tissues is unknown, we generated a Slc2a8 null mouse and characterized its phenotype. Slc2a8 knockout mice appeared healthy and exhibited normal growth, body weight development and glycemic control, indicating that GLUT8 does not play a significant role for maintenance of whole body glucose homeostasis.

Characterization of the human SLC2A11 (GLUT11) gene: alternative promoter usage, function, expression, and subcellular distribution of three isoforms, and lack of mouse orthologue.

GLUT11 (SLC2A11) is a class II sugar transport facilitator which exhibits highest similarity with the fructose transporter GLUT5 (about 42%). Here we demonstrate that separate exons 1 (exon 1A, exon 1B, and exon 1C) of the SLC2A11 gene generate mRNAs of three GLUT11 variants (GLUT11-A, GLUT11-B, and GLUT11-C) that differ in the amino acid sequence of their N-termini. All three 5'-flanking regions of exon 1A, exon 1B and exon 1C exhibited promoter activity when expressed as luciferase fusion constructs in COS-7 cells.

The glucose transporter families SGLT and GLUT: molecular basis of normal and aberrant function.

Glucose enters eucaryotic cells via 2 different types of membrane associated carrier proteins, the Na+-coupled glucose transporters (SGLT) and glucose transporter facilitators (GLUT). Three members of the SGLT family function as sugar transporters (SGLT1 and SGLT2) or sensors (SGLT3). The human GLUT family consists of 14 members, of which 11 have been shown to catalyze sugar transport.

The glucose transport facilitator GLUT8 is predominantly associated with the acrosomal region of mature spermatozoa.

The glucose transporter 8 (GLUT8) is a recently identified member of the family of sugar transport facilitators. In human tissues GLUT8 is predominantly expressed in testis in a gonadotropin-dependent manner. It is shown here that the onset of mRNA synthesis of GLUT8 during the maturation of mouse testis coincides with the appearance of mature spermatozoa.