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An annotated list of Ecuadorian butterflies (Lepidoptera: Papilionidae, Pieridae, Nymphalidae)
(2001)
Among the 13 genera and over 100 species of halfbeaks, three genera - Dermogenys, Nomorhamizphus and Hemirlzainplzodon - are internally fertilized and viviparous. These genera belong to a more inclusive clade, the Zenarchopterinae, that also includes Zenarchopterus, inferred to be internally fertilized and to lay fertilized eggs, and the monotypic Tondaiziclzthys, also inferred to be internally fertilized. Whereas the Hemiramphidae are distributed worldwide, internally fertilized halfbeaks are restricted to Southeast Asia. Recent data from histological surveys of the gonads of both males ancl females as well as cmbryonic modifications associated with viviparity have been combined here with osteological characters in a phylogenetic analysis. Results indicate overwhelming support for a sister-group relationship between Henzirhamnphodon and (Derinogeizys + Nomorhamnphus). Monophyly of the Dermogenys + Nomorhamphus clade is also well supported. These results confirm earlier suggestions that Dermnogenys, as previously defined, is paraphyletic. Within tlle Dermogenys+Noinorhamnphus clade, two monophyletic clades are supported: one comprises ten species including four new species (Dermogenys bruneiensis, Dermogenys robertsi, Dermogenys palawanensis and Dermogenys collettei) and the other comprises 13 species including three undescribed species (Nomorhamphus rossi, Nomorhamphus pinnimaculata and Nomorhainphus manifesta). Diagnoses for the species of Dermnogenys and Nomorhamnphus, as well as a natural classification for the included species, are presented.
The heat stress response is characterized by the presence of heat stress transcription factors (Hsfs) which mediate transcription of heat stress genes. In tomato (Lycopersicon peruvianum) cell cultures the simultaneous expression of four Hsfs, which are either constitutively (HsfA1 and HsfA3) or heat-stress inducible (HsfA2 and HsfB1) expressed, results in a complex network with dynamically changing cellular levels, intracellular localization and functional interactions. In order to examine the relevance of their multiplicity as well as to get more insights into the complexity of the plant heat stress response, the individual tomato Hsfs were investigated with respect to their protein interactions in vitro and in vivo. To this aim, I used pull-down assays as well as yeast assays to study the following aspects: 1. Oligomeric state of Hsfs: the results show that all class A Hsfs (HsfA1, HsfA2 and HsfA3) are trimeric proteins and interact with each other via the oligomerization (HR-A/B) domain. The similarity of their HRA/B regions allows formation of homo- and heterooligomeric complexes between all class A Hsfs. This special property was investigated by mutational studies with HsfA2 indicating that the linker and the HR-B regions are the minimal part required for Hsf/Hsf interactions. The conserved hydrophobic amino acid residues of the HR-B region are most important whereas the amino acid residues of the linker may provide higher flexibility to the HR-B region. Another investigated factor was HsfB1. HsfB1 is a member of class B Hsfs, which are characterized by an oligomerization domain without the 21 amino acid residues linker inserted between the HR-A and HR-B regions. It has a low activator potential and exists exclusively as dimer. HsfB1 can not physically interact with class A Hsfs. However, HsfB1 and HsfA1, binding to adjacent HSE sites, are assumed to cause strong synergistic effects in gene activation. 2. Potential HsfB1 interacting proteins: we searched for HsfB1 interacting proteins by using recombinant His-tagged proteins with HsfB1 as baits in pull-down assays. Histones H2A, H2B and H4 were identified by means of Peptide Mass Finger Printing and N-terminal sequencing analyses. The three histones represent the major proteins in tomato whole cell extracts retrieved by HsfB1. 3. HsfA2/small heat stress proteins (sHsps) interaction: pull-down and yeast two-hybrid assays were used to study the specific interaction of HsfA2 with tomato class II sHsp. This interaction occurs via the oligomerization domain of HsfA2. Other members of the plant Hsp20 family, including class I sHsp, do not interact with HsfA2. Heterooligomers of HsfA2 with class II sHsp may represent precursor forms of the plant higher molecular weight cytoplasmic complexes of heat stress granules, which form during heat stress. The findings presented in this thesis are a contribution to support the concept of a Hsfs network via protein-protein interactions. These data, together with information obtained from other studies, are used to propose a tentative model of the complex Hsfs network controlling the plant heat stress response.