Third International Congress of Histochemistry and Cytochemistry

Meiosis is critical for sexual reproduction. During meiosis, the dynamics and integrity of homologous chromosomes are tightly regulated. The genetic and molecular mechanisms governing these processes in vivo, however, remain largely unknown. In this study, we demonstrate that Bat3/Scythe is essential for survival and maintenance of male germ cells (GCs). Targeted inactivation of Bat3/Scythe in mice results in widespread apoptosis of meiotic male GCs and complete male infertility. Pachytene spermatocytes exhibit abnormal assembly and disassembly of synaptonemal complexes as demonstrated by abnormal SYCP3 staining and sustained γ-H2AX and Rad51/replication protein A foci. Further investigation revealed that a testis-specific protein, Hsp70-2/HspA2, is absent in Bat3-deficient male GCs at any stage of spermatogenesis; however, Hsp70-2 transcripts are expressed at normal levels. We found that Bat3 deficiency induces polyubiquitylation and subsequent degradation of Hsp70-2. Inhibition of proteasomal degradation restores Hsp70-2 protein levels. Our findings identify Bat3 as a critical regulator of Hsp70-2 in spermatogenesis, thereby providing a possible molecular target in idiopathic male infertility.

Degradation

10.1083/jcb.200802113

Cite

Citations (51)

HLA-B-associated transcript 3 (Bat3)/Scythe is essential for p300-mediated acetylation of p53

Genes & Development (2007)

Toru Sasaki Eugene Gan Andrew Wakeham Sally Kornbluth Tak W. Mak

In response to DNA damage, p53 undergoes post-translational modifications (including acetylation) that are critical for its transcriptional activity. However, the mechanism by which p53 acetylation is regulated is still unclear. Here, we describe an essential role for HLA-B-associated transcript 3 (Bat3)/Scythe in controlling the acetylation of p53 required for DNA damage responses. Depletion of Bat3 from human and mouse cells markedly impairs p53-mediated transactivation of its target genes Puma and p21 . Although DNA damage-induced phosphorylation, stabilization, and nuclear accumulation of p53 are not significantly affected by Bat3 depletion, p53 acetylation is almost completely abolished. Bat3 forms a complex with p300, and an increased amount of Bat3 enhances the recruitment of p53 to p300 and facilitates subsequent p53 acetylation. In contrast, Bat3-depleted cells show reduced p53–p300 complex formation and decreased p53 acetylation. Furthermore, consistent with our in vitro findings, thymocytes from Bat3-deficient mice exhibit reduced induction of puma and p21, and are resistant to DNA damage-induced apoptosis in vivo. Our data indicate that Bat3 is a novel and essential regulator of p53-mediated responses to genotoxic stress, and that Bat3 controls DNA damage-induced acetylation of p53.

10.1101/gad.1534107

Cite

Citations (125)

European Sweet Vernal Grasses (<I>Anthoxanthum</I>: Poaceae, Pooideae, Aveneae): A Morphometric Taxonomical Approach

Systematic Botany (2007)

Manuel Pimentel Graciela Estévez‐Pérez Elvira Sahuquillo

In the present study, several multivariate analyses were carried out to assess the taxonomic relationships among European species of the genus Anthoxanthum. A total of 1787 Anthoxanthum specimens representing all European taxa were analyzed. Thirty macro-morphological (13 quantitative and 17 qualitative) and 29 micro-morphological (7 quantitative and 22 qualitative) characters were considered. First, resemblances between specimens were established independently for macro- and micro-morphological characters using Gower's similarity coefficient, and were represented by means of principal coordinates and cluster analyses. Subsequently, different multivariate analyses were applied to quantitative and qualitative macromorphological data to determine the most discriminant characters and the accuracy of the present taxonomic structure of the genus. Finally, dissimilarities among groups of individuals -species and populations- were estimated using the information radius measure and then represented in different dendrograms. Within annuals, Anthoxanthum gracile is clearly differentiated morphologically, yet no compelling morphological differentiation can be found between Anthoxanthum aristatum and Anthoxanthum ovatum. Moreover, the definition of subspecies in the annual taxa is not supported by our results. Then, within perennials, although the morphological relationships among Anthoxanthum amarum, Anthoxanthum odoratum and Anthoxanthum alpinum have also been resolved, further research is needed to assess the taxonomic position of the Macaronesian endemic Anthoxanthum maderense.

Dendrogram

10.1600/036364407780360201

Cite

Citations (28)

Cytochemistry and Ultrastructure of the Mucilage Secreting Trichomes of Nymphoides peltata (Menyanthaceae)

Annals of Botany (1988)

M. Meyberg

The young developing leaves in the buds of Nymphoides peltata are covered by a hyaline mucilage. The mucilage contains free sugars, polysaccharides and proteins. The most abundant monosaccharides of the polysaccharide fraction are arabinose and galactose. Therefore, the major component of the mucilage is probably an arabinogalactan or arabinogalactan protein. The mucilage is secreted by glandular trichomes. It is suggested that both the polysaccharide and the protein fraction of the mucilage are transported to the plasmamembrane by vesicles of the Golgi apparatus (granulocrine secretion). Secretory proteins are probably synthesized in the rough endoplasmic reticulum and transported to the Golgi apparatus via transition vesicles. Polysaccharides were localized in Golgi vesicles by ultracytochemistry. After exocytosis the secretion is accumulated between the cell wall and the cuticle; this leads to the formation of protrusions on the outer walls of the glandular cells. Finally, the cuticle is ruptured and the secretion is released. The biological function of the mucilage is not known. Possibly the mucilage is a lubricant or a protection from desiccation.

Mucilage

Trichome

Arabinogalactan

Arabinose

10.1093/oxfordjournals.aob.a087690

Cite

Citations (35)

Ecological and evolutionary importance of neighbors in the grass Anthoxanthum odoratum

Oecologia (1990)

Gerrit A. J. Platenkamp T. C. Foin

Holcus lanatus

10.1007/bf00317753

Cite

Citations (21)

Anthoxanthum Mosaic Virus

Plant Pathology (1970)

P. L. Catherall

SUMMARY A hitherto unrecorded virus having flexible rod‐shaped particles about 740–760 × 13 nm was isolated from Anthoxanthum odoratwn L. It was transmitted by sap inoculation, but not by several species of insect, seed or soil to 18 species of Gramineae including wheat, oats and barley. In susceptible species the virus normally produced a mosaic mottling of the leaves which was sometimes followed by a necrotic streaking or striping.

Mosaic virus

10.1111/j.1365-3059.1970.tb00999.x

Cite

Citations (6)

Cloning and Characterization of Rat BAT3 cDNA

DNA and Cell Biology (1999)

Toshinori Ozaki Eiji Hanaoka Masahiko Naka Akira Nakagawara Shigeru Sakiyama

HLA-B-associated transcript 3 (BAT3) was originally identified as one of the genes located within human major histocompatibility complex. It encodes a large proline-rich protein with unknown function. In this study, we found that a fragment of the BAT3 gene product interacts with a candidate tumor suppressor, DAN, in the yeast-based two-hybrid system. We cloned the full-length rat BAT3 cDNA from a fibroblast 3Y1 cDNA library. Our sequence analysis has demonstrated that rat BAT3 cDNA is 3617 nucleotides in length and encodes a full-length BAT3 (1098 amino acids) with an estimated molecular mass of 114,801 daltons, which displays an 87.4% identity with human BAT3. The deletion experiment revealed that the N-terminal region (amino acid residues 1-80) of DAN was required for the interaction with BAT3. Green fluorescent protein-tagged BAT3 was largely localized in the cytoplasm of COS cells. Northern hybridization showed that BAT3 mRNA was expressed in all the adult rat tissues examined but predominantly in testis. In addition, the level of BAT3 mRNA expression was more downregulated in some of the transformed cells, including v-mos- and v-Ha-ras-transformed 3Y1 cells, than in the parental cells.

10.1089/104454999315222

Cite

Citations (21)

ON THE LIFE‐HISTORY OF “WIREWORMS” OF THE GENUS AGRIOTES ESCH.: PART IV.

Annals of Applied Biology (1928)

Austin Roberts

Summary. The most reliable characters for distinguishing the larva of Agriotes lineatus from the closely similar larva of A. obscurus have been found in the spiracles. The spiracles of A. lineatus are longer and more parallelsided than those of A. obscurus and also bear a noticeably larger number of teeth bordering the orifices.

10.1111/j.1744-7348.1928.tb07039.x

Cite

Citations (5)