The measurement of (86)Rb turnover recently has been suggested as a useful method for measuring field metabolic rate in small animals. We investigated a proposed mechanism of (86)Rb turnover, its analogy to K(+), by comparing the turnover of (86)Rb in a model insect, the rhinoceros beetle Xylotrupes gideon, fed a diet of plum jam or plum jam enriched with K(+) or Rb(+). The turnover of (86)Rb i...

Retinoblastoma (RB) is a malignant tumor of the retina seen in children, and potential non invasive biomarkers are in need for rapid diagnosis and for prognosticating the therapy. This study was undertaken to identify the differentially expressed miRNAs in the serum of children with RB in comparison with the normal age matched serum, to analyze its concurrence with the existing RB tumor miRNA p...

7-Hydroxystaurosporine (UCN-01), a protein kinase inhibitor in clinical development, demonstrates potent antineoplastic activity. To determine whether specific genetic abnormalities would modulate the response to UCN-01, a model of human non-small cell lung carcinoma (NSCLC) cell lines with differential abnormalities of p16CDKN2, RB, and p53 was used for these studies. Cell growth was measured ...

The retinoblastoma protein (Rb), an important ubiquitous cell cycle regulator, was initially identified as the retinoblastoma tumor suppressor. To further address the activities of Rb in proliferation and tumorigenesis in the hematopoietic lineage, we transplanted Rb-/- fetal liver cells into sibling mice and assessed the outcome of Rb-/- hematopoietic cells in both short-term and long-term stu...

The product of the retinoblastoma susceptibility gene RB1 (Rb) is likely to function as an inhibitor of cell growth. Previous studies have suggested that certain growth-suppressing effects of Rb are exerted in G0/G1 phase and that phosphorylation can inactivate these functions. We tested this hypothesis by examining the expression and state of phosphorylation of Rb in several lineages of primar...

The retinoblastoma protein (RB) represses RNA polymerase III transcription effectively both in vivo and in vitro. Here we demonstrate that the general transcription factors snRNA-activating protein complex (SNAP(c)) and TATA binding protein (TBP) are important for RB repression of human U6 snRNA gene transcription by RNA polymerase III. RB is associated with SNAP(c) as detected by both coimmuno...

Introduction of the normal retinoblastoma gene (RB) into different tumor cells possessing inactivated RB genes suppresses their tumorigenicity in nude mice. These results suggest that RB replacement is a potential strategy for developing future clinical treatments of cancer. In a transgenic mouse model, we found that the quantity of RB protein in a given cell may play an important role in dicta...

We have characterized the convoluted ruffled border (RB) membrane that an activated osteoclast maintains against the bone matrix. The bulk of both lgp110 and rab7, a small GTP-binding protein participating in vesicle fusion to late endosomes, was localized to the RB. This indicates that the membrane has some characteristics of late endosomal membranes in other cells. Furthermore, the bulk of me...