Rap2 belongs to the Ras family of small GTP-binding proteins, but its specific roles in cell signaling remain unknown. In the present study, we have affinity-purified from rat brain a Rap2-interacting protein of ϳ155 kDa, p155. By liquid chromatography tandem mass spectrometry, we have identified p155 as Traf2-and Nck-interacting kinase (TNIK). TNIK possesses an N-terminal kinase domain homologous to STE20, the Saccharomyces cerevisiae mitogen-activated protein kinase kinase kinase kinase, and a C-terminal regulatory domain termed the citron homology (CNH) domain. TNIK induces disruption of F-actin structure, thereby inhibiting cell spreading. In addition, TNIK specifically activates the c-Jun N-terminal kinase (JNK) pathway. Among our observations, TNIK interacted with Rap2 through its CNH domain but did not interact with Rap1 or Ras. TNIK interaction with Rap2 was dependent on the intact effector region and GTP-bound configuration of Rap2. When co-expressed in cultured cells, TNIK colocalized with Rap2, while a mutant TNIK lacking the CNH domain did not. Rap2 potently enhanced the inhibitory function of TNIK against cell spreading, but this was not observed for the mutant TNIK lacking the CNH domain. Rap2 did not significantly enhance TNIKinduced JNK activation, but promoted autophosphorylation and translocation of TNIK to the detergentinsoluble cytoskeletal fraction. These results suggest that TNIK is a specific effector of Rap2 to regulate actin cytoskeleton.Rap2 is a member of the Ras family of small GTP-binding proteins, which regulate a range of cellular processes including cell proliferation, differentiation, and cytoskeletal rearrangement (for a review, see Ref. 1). To regulate these processes, Ras family proteins cycle between GTP-bound active and GDPbound inactive forms. In the GTP-bound active form, Ras family proteins physically interact with downstream effectors and thereby regulate their subcellular localization and activity (1). For instance, GTP-bound Ras interacts with effectors including Raf-1, B-raf, Ral guanine nucleotide dissociation stimulator During interaction with effectors, the effector regions of Ras family proteins (amino acids 32-40 in the case of Ras) serve as binding interfaces; thus, mutations within their effector regions impair interaction with effectors (Refs. 1-4, reviewed in Ref. 6). The effector regions are also critical for the differential recognition of effectors. For instance, the effector region of Rap1, a close relative of Rap2, is identical to that of Ras. Rap1 interacts with effectors of Ras, and sometimes counteracts Rasmediated signaling (1, 2). For example, Rap1 regulates the extracellular signal-regulated kinase (ERK) pathway, the "classical" mitogen-activated protein kinase (MAPK) pathway, through Raf-1 and B-raf. Although Rap1 interacts with Raf-1 and B-raf, it only activates B-raf. In fibroblasts, Rap1 inhibits Ras-induced cellular transformation. Rap1 exerts this action presumably by trapping Raf-1 in an inactive complex, thereby inhibiting ERK activation (1...

The surveillance of prevalent Leishmania and sand fly species in endemic areas is important for prediction of the risk and expansion of leishmaniasis. In this study, we developed a polymerase chain reaction (PCR)-based method for detection of Leishmania minicircle DNA within individual sand flies. Using this method, we detected minicircle DNA in 6 (3.3%) of 183 sand flies, while 5 (3.5%) of 143 were positive for Leishmania promastigotes in the same areas by microscopic examination. The species were identified as Leishmania (Leishmania) mexicana by nucleotide sequencing of the cytochrome b gene. Additionally, all the Leishmania-positive sand flies were identified as Lutzomyia ayacuchensis by the restriction enzyme digestion of the PCR-amplified 18S ribosomal RNA gene fragments. Since this combined method is relatively easy and can process a large number of samples, it will be a powerful tool for the rapid identification of prevalent sand fly and Leishmania species as well as monitoring the infection rate in sand fly populations in endemic areas.

S U M M A R YThe Cytochrome b (Cyt b) gene has proved to be useful for identification and classification of many mammals and plants. In order to evaluate the utility of this gene for discrimination of Leishmania parasites as well as for exploring their phylogenetic relationships, we determined the nucleotide sequences of the Cyt b gene from 13 human-infecting Leishmania species (14 strains) from the New and Old Worlds. The Cyt b genes, approximately 1080 base pairs, were found to be A/T rich, and their 5k terminal-editing regions were highly conserved. The nucleotide sequence variation among them was enough to discriminate parasite species; 245 nucleotide positions were polymorphic and 190 positions were parsimony informative. The phylogenetic relationships based on this gene, showed good agreement with the classification of Lainson & Shaw (1987) ) tropica complex and the placement of L. tarentolae in another genus. These data show that the Cyt b gene is useful for phylogenetic study of Leishmania parasites.

The observed number of patients was moderately large, thus indicating a high incidence of cutaneous tuberculosis in Larkana. Lupus vulgaris, a form of cutaneous tuberculosis, was widespread in this area and prevalent in adults, while scrofuloderma was prevalent in children. Moreover, the existing rate of the disease was higher in children aged under 10 years and lower in adults. This indicates that children are more prone to this disease than adults.

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Abstract. Between 1986 and 1988,epidemiologic

There have been no large-scale epidemiological studies of human papillomavirus (HPV) genotype distribution of common warts in Japan. A total of 213 patients with common warts (104 males and 109 females) in Japan were studied to detect HPV genotype distribution by polymerase chain reaction (PCR) and direct sequencing analysis. The results were as follows: 94 HPV-1a (44.1%), 35 HPV-4 (16.4%), 30 HPV-65 (14.1%), 13 HPV-27 (6.1%), 13 HPV-2a (6.1%), 9 HPV-57b (4.22%), 3 HPV-16 (1.41%), 2 HPV-6a (0.94%), 2 HPV-63 (0.94%), and 1 case for each of HPV-3, -5, -5b, -7, -10, -21, -29, -47, -56, -57, -62, and -92 (0.47%, respectively). Four cases (1.88%) were found in which two different HPV types were detected within the lesions: one case of HPV-1a with HPV-16, one case of HPV-1a with HPV-65, one case of HPV-6a with HPV-8, and one case of HPV-65 with HPV-16. There were seven cases of mucosal types (3.3%), that is, two HPV-6a, three HPV-16, one HPV-56, and one HPV-62, and three cases of epidermodysplasia verruciformis (EV)-related types (1.41%), that is, one HPV-5, one HPV-5b (both of which belonged to a high-risk group), and one HPV-47 (which belonged to a low-risk group). To date, this is the largest sequencing-based study of HPV for common warts in Japan. It is said that common warts are induced predominantly by HPV-2, -27, and -57 in European population. However, the present results showed that in Japan they were induced mostly by HPV-1, -4, and -65. This suggests that regional differences in HPV genotype distribution may exist between European and Japanese populations.

In recent times, there has been an increase in the number of reports for new and rare variants of cutaneous leishmaniasis (CL). Here, we describe three unusual clinical forms of CL identified in Ecuadorian children. A total of 131 patients with CL were diagnosed over a 2-year period of active search. In 3 (2.29%), the lesions were very unusual; these included erysipeloid, recidiva cutis (LRC), and disseminated leishmaniasis (DL). The erysipeloid case is characterized by erythematous and indurated plaque seen on the face of a 5-year-old boy; the LRC one is differentiated by slowly progressing red-brown papules around large scars of healed sores in a 6-year-old girl, and the DL case is characterized by dozens of cutaneous ulcers distributed in the whole body of a 1-year-old girl. Leishmania parasites were isolated by lesion aspirate and analyzed by the technique multilocus enzyme electrophoresis (MLEE). All three isolates were identified as Leishmania (Viannia) panamensis. These distinct clinical variants rarely have been reported previously in the American cutaneous leishmaniasis, and for the first time L. (V.) panamensis was identified as the etiologic agent. Our cases extend the spectrum of clinical presentations in New World leishmaniasis.