A revision of the genus Telomerina Roháček (Diptera, Sphaeroceridae)

Abstract. The genus Telomerina Roháč;ek (Diptera: Sphaeroceridae) is revised to include twelve species: five Palaearctic, five Nearctic, one Holarctic and one cosmopolitan. The five Neartic species, chillcotti, orpha, submerda, carta and pengellyi are described as new. The male of T.eburnea Roháček is described; T.gracilipennis (Spuler) is synonomized with T.flavipes (Meigen) and T.antonini Roháček is synonomized with T.levifrons (Spuler). The larva and pupa of T.flavipes are described. A phylogenetic hypothesis for the genus is presented along with a discussion of its zoogeography.     

Revisiting Hrdlička and Boas: Asymmetries of Race and Anti-Imperialism in Interwar Anthropology

ABSTRACT  Physical anthropologist Aleš Hrdlička is often remembered as an institutional and political opponent of Franz Boas and as an advocate of racial typology against which the Boasian antiracialist position in American anthropology developed. I argue that Hrdlička nonetheless also has more subtle lessons to offer about the political limits of Boasian antiracism. Examining Hrdlička's engagement with the politics of Europe and East Asia from the 1920s to the 1940s, particularly with the intellectual grounding of Japanese imperialism, I suggest that he was perhaps uniquely cognizant of a "second problem of race in the world"—the racist assimilationism of the Japanese empire—vis-à-vis the Boasian grasp of race, rooted in a response to U.S. and Nazi racisms, as a category of invidious difference. Moreover, I contend that the lacuna that Hrdlička helps us identify has continued to haunt the discipline at certain key moments of Boasian critique of other ideological forces.     

The Retention of Folk Linguistic Concepts and the ti'yčir Caste in Contemporary Nacireman Culture

Certain structural features of spoken Nacireman are examined both objectively and from the point of view of native Nacireman folk linguistics. Discrepancies on the phonological, morphological, and syntactic levels between the traditional folk analysis and that of modern structural linguistics are accounted for in terms of the cognitive structure and ideological orientation of the ti'čir caste, which plays a critical role in the enculturation of Nacireman children, and in terms of the internal organization and external relationships of the native academic institutions, whose function in Nacireman society can be specified only after intensive deep-structure analysis.     

Monomeric sarcosine oxidase: role of histidine 269 in catalysis

Conservative mutation of His269 (to Asn, Ala, or Gln) does not-significantly affect the expression of monomeric sarcosine oxidase (MSOX), covalent flavinylation, the physicochemical properties of bound FAD, or the overall protein structure. Turnover with sarcosine and the limiting rate of the reductive half-reaction with L-proline at pH 8.0 are, however, nearly 2 orders of magnitude slower than that with with wild-type MSOX. The crystal structure of the His269Asn complex with pyrrole-2-carboxylate shows that the pyrrole ring of the inhibitor is displaced as compared with wild-type MSOX. The His269 mutants all form charge-transfer complexes with pyrrole-2-carboxylate or methylthioacetate, but the charge-transfer bands are shifted to shorter wavelengths (higher energy) as compared with wild-type MSOX. Both wild-type MSOX and the His269Asn mutant bind the zwitterionic form of L-proline. The E(ox).L-proline complex formed with the His269Asn mutant or wild-type MSOX contains an ionizable group (pK(a) = 8.0) that is required for conversion of the zwitterionic L-proline to the reactive anionic form, indicating that His269 is not the active-site base. We propose that the change in ligand orientation observed upon mutation of His269 results in a less than optimal overlap of the highest occupied orbital of the ligand with the lowest unoccupied orbital of the flavin. The postulated effect on orbital overlap may account for the increased energy of charge-transfer bands and the slower rates of electron transfer observed for mutant enzyme complexes with charge-transfer ligands and substrates, respectively.     

Kinase suppressor of Ras signals through Thr269 of c-Raf-1

We recently established a two-stage in vitro assay for KSR kinase activity in which KSR never comes in contact with any recombinant kinase other than c-Raf-1 and defined the epidermal growth factor (EGF) as a potent activator of KSR kinase activity (Xing, H. R., Lozano, J., and Kolesnick, R. (2000) J. Biol. Chem. 275, 17276-17280). That study, however, did not address the mechanism of c-Raf-1 stimulation by activated KSR. Here we show that phosphorylation of c-Raf-1 on Thr(269) by KSR is necessary for optimal activation in response to EGF stimulation. In vitro, KSR specifically phosphorylated c-Raf-1 on threonine residues during the first stage of the two-stage kinase assay. Using purified wild-type and mutant c-Raf-1 proteins, we demonstrate that Thr(269) is the major c-Raf-1 site phosphorylated by KSR in vitro and that phosphorylation of this site is essential for c-Raf-1 activation by KSR. KSR acts via transphosphorylation, not by increasing c-Raf-1 autophosphorylation, as kinase-inactive c-Raf-1(K375M) served as an equally effective KSR substrate. In vivo, low physiologic doses of EGF (0.001-0.1 ng/ml) stimulated KSR activation and induced Thr(269) phosphorylation and activation of c-Raf-1. Low dose EGF did not induce serine or tyrosine phosphorylation of c-Raf-1. High dose EGF (10-100 ng/ml) induced no additional Thr(269) phosphorylation, but rather increased c-Raf-1 phosphorylation on serine residues and Tyr(340)/Tyr(341). A Raf-1 mutant with valine substituted for Thr(269) was unresponsive to low dose EGF, but was serine- and Tyr(340)/Tyr(341)-phosphorylated and partially activated at high dose EGF. This study shows that Thr(269) is the major c-Raf-1 site phosphorylated by KSR. Furthermore, phosphorylation of this site is essential for c-Raf-1 activation by KSR in vitro and for optimal c-Raf-1 activation in response to physiologic EGF stimulation in vivo.