0000000000134697
AUTHOR
Wolfgang Hennig
Arthropod 7SK RNA
The 7SK small nuclear RNA (snRNA) is a key player in the regulation of polymerase (pol) II transcription. The 7SK RNA was long believed to be specific to vertebrates where it is highly conserved. Homologs in basal deuterostomes and a few lophotrochozoan species were only recently reported. On longer timescales, 7SK evolves rapidly with only few conserved sequence and structure motifs. Previous attempts to identify the Drosophila homolog thus have remained unsuccessful despite considerable efforts. Here we report on the discovery of arthropod 7SK RNAs using a novel search strategy based on pol III promoters, as well as the subsequent verification of its expression. Our results demonstrate th…
Molecular biology, China and the West
More than 15 years ago, in November 1985, I travelled to China for the first time. I joined a symposium on developmental biology in the Shanghai Institute of Cell Biology (CBI), organised by the Chinese Academy of Sciences and the Max‐Planck‐Gesellschaft in Germany. The symposium was meant to provide perspectives for the future of the Max Planck Guest Laboratory, just founded in the CBI. When I attended, I did not anticipate that my visit to Shanghai would initiate a long‐term commitment to China. I did not even expect to return to China in the near future. But early in 1987, my colleague Uli Schwarz from the Max Planck Institute of Developmental Biology in Tubingen, who was and still is in…
Vererbung als biologisches Grundphänomen
Verfolgt man die Unterschiede in der Auspragung einzelner Merkmale eines Individuums uber mehrere Nachkommengenerationen hinweg, so zeigt es sich, das bestimmte Eigenschaften genetisch eindeutig festgelegt sind. In Individuen verschiedener aufeinanderfolgender Generationen treten sie stets wieder in gleicher Art und Weise auf. Mendel hat sich diese Beobachtung zunutze gemacht und durch konsequente Kreuzungsanalysen von Pflanzen mit ausgewahlten Merkmalen die Grundregeln der Vererbung erkannt.
Research in China
My stay in China began in November 1985 with a lecture at the opening of the Max Planck Guest Laboratory in the Institute of Cell Biology at the Chinese Academy of Sciences (CAS) in Shanghai (Hennig, 2000). It marked the beginning of 23 years of research and teaching at the Institute of Cell Biology and other universities throughout China. > Looking back after 23 years, the changes that have taken place in China could not have been predicted in 1985… In January 2001, I accepted a long‐term lectureship offered by the German Academic Exchange Service (DAAD; Bonn, Germany), which, with further support from CAS, allowed me to create my own research group within the Shanghai Institutes for Biolo…
Das menschliche Genom
Durch die Entwicklung gentechnologischer Methoden hat die Humangenetik einen revolutionaren Wandel erlebt. Durch die nunmehr vollstandige Sequenzierung des menschlichen Genoms konnen menschliche Gene identifiziert und ihre Funktion untersucht werden. Bereits vor der Vollendung der Sequenzierung des menschlichen Genoms im Human Genome Project war es gelungen, eine Anzahl von Genen zu isolieren, deren Mutation schwere Erbkrankheiten zur Folge hat. Die molekulare Analyse dieser Gene hat nicht nur neue Einsichten in die molekulare Struktur von Genen vermittelt, sondern sie hat auch zur Identifikation von Genen gefuhrt, die an der Entstehung von Tumoren beteiligt sind. Oft handelt es sich hierbe…
Molekulare Struktur des eukaryotischen Genoms
Nachdem es gelungen war, die Grundprinzipien der Vererbung und der Umsetzung von Erbinformation zur Nutzung in der Zelle bis zur molekularen Ebene hin aufzuklaren, stellte sich die Frage nach den Eigenschaften und der Zahl der Gene sowie nach der Art ihrer Anordnung in den Chromosomen. Ausgangspunkt fur solche Analysen war die Untersuchung der molekularen Struktur des Genoms. Hierbei machte man die unerwartete Entdeckung, das das eukaryotische Genom zum grosten Teil nicht aus proteinkodierenden DNA-Sequenzen besteht. Ein groser Teil der DNA-Sequenzen gehort zu einer Klasse von DNA, die man als repetitive DNA bezeichnet, da sie in vielen, teils identischen, teils strukturell voneinander abwe…
Histone modifications in the male germ line of Drosophilaa
Abstract Background In the male germ line of Drosophila chromatin remains decondensed and highly transcribed during meiotic prophase until it is rapidly compacted. A large proportion of the cell cycle-regulated histone H3.1 is replaced by H3.3, a histone variant encoded outside the histone repeat cluster and not subject to cell cycle controlled expression. Results We investigated histone modification patterns in testes of D. melanogaster and D. hydei. In somatic cells of the testis envelope and in germ cells these modification patterns differ from those typically seen in eu- and heterochromatin of other somatic cells. During the meiotic prophase some modifications expected in active chromat…
RADHA - a new male germ line-specific chromosomal protein of Drosophila
A new chromosomal protein - RADHA - of Drosophila is described that is specific for the male germ line. It is encoded by a single-copy gene, located in the region 96C-D of D. melanogaster polytene chromosomes. Transcription of the radha gene is restricted to the primary spermatocyte stage. The protein initially accumulates in some of the Y-chromosomal lampbrush loops. After meiosis it is found in the nuclei of spermatids and might be involved in chromatin rearrangement processes in the male germ line. RADHA is a basic protein with a C-terminal leucine zipper region and several segments capable of forming coiled-coil structures.
Naturally occurring testis-specific histone H3 antisense transcripts inDrosophila
While analysing the transcription of the cluster of cell-cycle regulated histone genes in Drosophila hydei, we have found transcripts spanned both histone H3 and H4 genes and were antisense for histone H3. As the two histone genes are in opposite orientation, these transcripts contained the sense strand of the histone H4 gene. Such transcripts were present in both poly(A) + and poly(A) - RNA fractions. The polyadenylated molecules contained a poly(A) tail at the 3' end of the stem-loop structure, which is characteristic for cell-cycle regulated histone mRNAs. The antisense RNA of histone H3 is synthesized exclusively in testes. By developing an improved protocol of in situ hybridization to …
Drosophila melanogaster histone H2B retropseudogene is inserted into a region rich in transposable elements.
We have isolated and characterized the genomic sequence of a Drosophila melanogaster histone H2B pseudogene that is localized outside of the cluster of the replication-dependent histone genes and has all the properties of a retropseudogene. It is highly homologous to the transcribed region of the D. melanogaster histone H2B gene, but not to its flanking regions, and is surrounded by short direct repeats. The pseudogene contains several point mutations that preclude its translation. The sequence of the 3' region of this pseudogene is compatible with the hypothesis that the 3' terminal stem-loop structure of the histone H2B mRNA has served as a primer for the reverse transcription event from …
Comment on the editorial ‘The secret ways of scientists’ in EMBO reports , December 2000
I read ‘The secret ways of scientists’ with much interest and in principle I closely share the view expressed there. However, I am rather suspicious that such a view no longer reflects the truth. It appears to me that the tendency among scientists to start their own biotech companies may lead to a corruption of values and create a rather strange mixture of attitudes. The editorial states that ‘our …