The scaffold protein c-Jun NH2-terminal kinase-associated leucine zipper protein regulates cell migration through interaction with the G protein G(alpha 13)

Scaffold proteins for MAP kinase (MAPK) signalling modules play an important role in the specific and efficient signal transduction of the relevant MAPK cascades. Here, we investigated the function of the scaffolding protein c-Jun NH(2)-terminal kinase (JNK)-associated leucine zipper protein (JLP) by depleting it in cultured cells using a short hairpin RNA (shRNA) against human JLP. HeLa and DLD-1 cells stably expressing the shRNA showed a defect in cell migration. The re-expression of full-length shRNA-resistant mouse JLP rescued the impaired cell migration of the JLP-depleted HeLa cells; whereas, a C-terminal deletion mutant of mouse JLP, which failed to bind the G protein G(alpha13), showed little or no effect on the cell migration defect. Furthermore, although a constitutively active G(alpha13) enhanced the migration of control HeLa cells, the G(alpha13)-induced cell migration was significantly suppressed in the JLP-depleted HeLa cells. Taken together, these results suggest that JLP regulates cell migration through an interaction with G(alpha13).     

The Leiognathus splendens complex (Perciformes: Leiognathidae) with the description of a new species, Leiognathus kupanensis Kimura and Peristiwady

Taxonomic analysis of a group of morphologically similar ponyfishes (Perciformes: Leiognathidae) establishes the Leiognathus splendens complex comprising four valid species: L. jonesi James, 1971, widely distributed in the Indo-West Pacific, from Mauritius to Papua New Guinea, north to Hainan I. (China), and south to Brisbane, Australia; L. kupanensis sp. nov., currently known only from Kupang, Timor, Indonesia; L. rapsoni Munro, 1964, currently known only from India, Indonesia, and Papua New Guinea, and L. splendens Cuvier, 1829, widely distributed in the eastern Indian and western Pacific oceans, from India to Papua New Guinea, and from southern Japan to northern Australia. The L. splendens complex can be defined by the following combination of characters: body depth 42–60% of standard length; mouth protruding downward; slender, minute teeth uniserially on jaws; lower margin of orbit above the horizontal through the gape when mouth closed; breast almost completely scaled; lateral line complete, and a dark blotch on top of spinous dorsal fin. Diagnostic characters of the members are as follows: L. jonesi—anterior dorsolateral body surface with a semicircular naked area on nape, and a paler dark blotch on spinous dorsal fin; L. kupanensis—anterior dorsolateral body surface widely naked; L. rapsoni—cheek scaled; L. splendens—anterior dorsolateral body surface completely scaled and a jet black blotch on spinous dorsal fin.     

Hemitriakis complicofasciata, a new whitefin topeshark (Carcharhiniformes: Triakidae) from Japan

Hemitriakis complicofasciata sp. nov. is described from 18 specimens from the waters of the Ryukyu Islands, southern Japan. This new species is distinguishable from other congeners by the following characters: higher vertebral counts (46–52 monospondylous vertebrae and 124–131 precaudal total vertebrae), presence of a developed posterior nasal flap, first dorsal fin origin anterior to free rear tips of pectoral fin, shorter snout length (snout tip to oral length less than 1.8 times internarial width), absence of an accessory cartilage at symphysial part of upper jaw, and dark complicated lines and rings on embryos and juveniles.     

Hepatitis C virus (HCV) NS5A binds RNA-dependent RNA polymerase (RdRP) NS5B and modulates RNA-dependent RNA polymerase activity.

Hepatitis C virus (HCV) NS5B is RNA-dependent RNA polymerase (RdRP), the essential catalytic enzyme for HCV replication. Recently, NS5A has been reported to be important for the establishment of HCV replication in vitro by the adaptive mutations, although its role in viral replication remains uncertain. Here we report that purified bacterial recombinant NS5A and NS5B directly interact with each other in vitro, detected by glutathione S-transferase (GST) pull-down assay. Furthermore, complex formation of these proteins transiently coexpressed in mammalian cells was detected by coprecipitation. Using terminally and internally truncated NS5A, two discontinuous regions of NS5A (amino acids 105-162 and 277-334) outside of the adaptive mutations were identified to be independently essential for the binding both in vivo and in vitro (Yamashita, T., Kaneko, S., Shirota, Y., Qin, W., Nomura, T., Kobayashi, K., and Mkyrakami, S. (1998) J. Biol. Chem. 273, 15479-15486). We previously examined the effect of His-NS5A on RdRP activity of the soluble recombinant NS5Bt in vitro (see Yamashita et al. above). Wild NS5A weakly stimulated at first (when less than 0.1 molar ratio to NS5B) and then inhibited the NS5Bt RdRP activity in a dose-dependent manner. The internal deletion mutants defective in NS5B binding exhibited no inhibitory effect, indicating that the NS5B binding is necessary for the inhibition. Taken together, our results support the idea that NS5A modulates HCV replication as a component of replication complex.     

Developmental morphology of the cyprinid fish, Candidia barbatus

 Embryonic, larval, and juvenile development of a Taiwanese cyprinid fish, Candidia barbatus, is described from laboratory-reared specimens. The eggs, measuring 1.8–2.1 mm in diameter, were demersal, almost spherical in shape, transparent and unpigmented, with a pale yellow yolk and no oil globule. Hatching occurred 56–69 h after fertilization, the newly hatched larvae measuring 4.9–5.3 mm in body length (BL) with 25–26 + 13–14 = 39–40 myomeres. The yolk was completely absorbed at 7.6 mm BL. Notochord flexion was initiated at 6.8 mm BL and finished at 7.6 mm BL. Aggregate numbers of all fin rays were completed at 12 mm BL. Barbels on the upper jaw appeared near the corner of the mouth at 17 mm BL. Eggs of the species closely resembled those of its related cyprinid genera, Opsariichthys and Zacco. Larvae and juveniles of C. barbatus were similar to those of O. uncirostris subspp., Z. platypus, and Z. pachycephalus, but differed from the latter in the process of disappearance of the adipose finfold (postflexion larval stage), barbels on upper jaw (juvenile stage), and pigmentation on the lateral body surface (postflexion larval and juvenile stages). Although C. barbatus also differed from the Z. temminckii species' group [Z. temminckii and Zacco sp. (sensu Hosoya, 2002)] in having barbels, larvae and juveniles of the former showed more similarity to the latter species group than to O. uncirostris subspp., Z. platypus, and Z. pachycephalus, from the aspect of head and body pigmentation.     

Gerres limbatus Cuvier and G. lucidus Cuvier from the Indo-Malay Archipelagos, the latter corresponding to young of the former (Perciformes: Gerreidae)

Taxonomic status of Gerres limbatus Cuvier in Cuvier and Valenciennes, 1830 and G. lucidus Cuvier in Cuvier and Valenciennes, 1830 was studied. The two species were reassessed as the same species, the latter corresponding to young of the former, on the basis of examination of their eight syntypes and other comparative specimens. Gerres limbatus clearly differs from other congeners in having 2½–3 (usually 2½) scales between the 5th dorsal fin spine base and the lateral line, and four or five diffuse, dark saddle patches mainly along the back in life (more apparent in small specimens less than ca. 65 mm in standard length, or preserved and stressed live specimens) (vs. usually more than 3½ scales between fifth dorsal fin spine base and lateral line, and and no such body color pattern of G. limbatus in other congeners). The species is currently known from the southern and western coasts of India including Sri Lanka, the Malay Peninsula, Gulf of Thailand, and Indonesia, becoming rare in occurrence eastward.     

A new species, Gazza squamiventralis, from the East Coast of Africa (Perciformes: Leiognathidae)

Gazza squamiventralis sp. nov. is described as the fifth species of the genus, based on the holotype and eight paratypes, 42–96 mm in standard length, collected along the east coast of Africa, from Kenya to Mozambique. The species is similar to other congeners in general appearance, differing clearly from them in having the ventrolateral surface of the body scaled anterior to a line from the pectoral fin base to the pelvic fin origin (vs naked) and a smooth supraorbital ridge (vs finely serrated). Additionally, the species differs from G. dentex, G. rhombea, and G. achlamys in having the dorsolateral surface of the body scaled anterior to a vertical through the tip of the posterior branch of the supratemporal canal (vs corresponding region naked), and from G. minuta in having the first dorsal fin pterygiophore narrowly expanded anteriorly, with a concave margin (vs broadly expanded, with a convex or linear margin), and a short antrorse extension of the first anal fin pterygiophore (vs long). A key to the five species of the genus Gazza is provided. Received: May 30, 2000 / Revised: September 16, 2000 / Accepted: January 16, 2001     

Polydactylus bifurcus, a new species of threadfin from Lombok Island, Indonesia (Perciformes: Polynemidae)

Polydactylus bifurcus sp. nov. is described on the basis of a single specimen collected from Lombok Island, Indonesia. The new species is distinguished from all other Indo-Pacific Polydactylus species by the following combination of characters: 15 pectoral fin rays, 5 pectoral filaments, 69 pored lateral line scales, 30 gill rakers, second spine of first dorsal fin very strong and lateral line bifurcated on caudal fin base, extending to posterior margins of upper and lower caudal fin lobes. Received: October 19, 2000 / Revised: April 21, 2001 / Accepted: April 25, 2001