Note on occurrence of Mymaromella pala Huber and Gibson (Hymenoptera: Mymarommatidae) in Montana: a new state record

The parasitic wasp Mymaromella pala Huber and Gibson (Hymenoptera: Mymarommatidae) was collected at 4 sites within a canyon reach of the Kootenai River in Lincoln County, Montana. This minute species has only recently been described, but it appears to have a large distribution throughout the United States and to be associated with upland and riparian forests. La avispa parasitaria Mymaromella pala Huber y Gibson (Hymenoptera: Mymarommatidae) se recolectó en cuatro sitios a lo largo de un cañón del Río Kootenai en Lincoln Co., MT. Hace poco que se describió esta especie diminuta, pero parece tener una distribución extensa en los EE.UU. y estar asociada con bosques altos y ribereños.     

Breeding behavior of the Plumbeous Vireo in New Mexico

The Plumbeous Vireo ( Vireo plumbeus ) is a poorly studied songbird species that breeds within the interior western United States and Mexico. We studied the breeding behavior of Plumbeous Vireos within pinyon-juniper habitats in northeastern New Mexico in 1996 and 1997. Over both years we located and monitored 40 nests and conducted behavioral observations throughout the nesting cycle. From these observations we described and compared basic behavioral traits of male and female vireos during their nest-building, egg-laying, incubation, and nestling stages, and their response to potential predators near the nest. Male vireos displayed potential nest sites to females, but the females selected the site to be used and built most of the nest. Vireos often did not initiate egg-laying until 2-3 d after nest completion. The female tended to incubate eggs and brood nestlings more than the male, but both parents contributed equally in provisioning the young. Brown-headed Cowbirds ( Molothrus ater ) parasitized 77% of nests in 1996, 63% in 1997, and parasitism was the primary cause of nest failure in this population. The conspicuousness of vireos around the nest, particularly during the nest-building stage, may contribute to high parasitism levels. Vireo aggression near the nest may also act as a cue to help cowbirds locate nests.     

Genome-wide association study of leaf architecture in the maize nested association mapping population

US maize yield has increased eight-fold in the past 80 years, with half of the gain attributed to selection by breeders. During this time, changes in maize leaf angle and size have altered plant architecture, allowing more efficient light capture as planting density has increased. Through a genome-wide association study (GWAS) of the maize nested association mapping panel, we determined the genetic basis of important leaf architecture traits and identified some of the key genes. Overall, we demonstrate that the genetic architecture of the leaf traits is dominated by small effects, with little epistasis, environmental interaction or pleiotropy. In particular, GWAS results show that variations at the liguleless genes have contributed to more upright leaves. These results demonstrate that the use of GWAS with specially designed mapping populations is effective in uncovering the basis of key agronomic traits.     

Common variants at MS4A4/MS4A6E, CD2AP, CD33 and EPHA1 are associated with late-onset Alzheimer's disease

The Alzheimer Disease Genetics Consortium (ADGC) performed a genome-wide association study of late-onset Alzheimer disease using a three-stage design consisting of a discovery stage (stage 1) and two replication stages (stages 2 and 3). Both joint analysis and meta-analysis approaches were used. We obtained genome-wide significant results at MS4A4A (rs4938933; stages 1 and 2, meta-analysis P (P(M)) = 1.7 × 10(-9), joint analysis P (P(J)) = 1.7 × 10(-9); stages 1, 2 and 3, P(M) = 8.2 × 10(-12)), CD2AP (rs9349407; stages 1, 2 and 3, P(M) = 8.6 × 10(-9)), EPHA1 (rs11767557; stages 1, 2 and 3, P(M) = 6.0 × 10(-10)) and CD33 (rs3865444; stages 1, 2 and 3, P(M) = 1.6 × 10(-9)). We also replicated previous associations at CR1 (rs6701713; P(M) = 4.6 × 10(-10), P(J) = 5.2 × 10(-11)), CLU (rs1532278; P(M) = 8.3 × 10(-8), P(J) = 1.9 × 10(-8)), BIN1 (rs7561528; P(M) = 4.0 × 10(-14), P(J) = 5.2 × 10(-14)) and PICALM (rs561655; P(M) = 7.0 × 10(-11), P(J) = 1.0 × 10(-10)), but not at EXOC3L2, to late-onset Alzheimer's disease susceptibility.     

Truncating mutations in the last exon of NOTCH2 cause a rare skeletal disorder with osteoporosis

Hajdu-Cheney syndrome is a rare autosomal dominant skeletal disorder with facial anomalies, osteoporosis and acro-osteolysis. We sequenced the exomes of six unrelated individuals with this syndrome and identified heterozygous nonsense and frameshift mutations in NOTCH2 in five of them. All mutations cluster to the last coding exon of the gene, suggesting that the mutant mRNA products escape nonsense-mediated decay and that the resulting truncated NOTCH2 proteins act in a gain-of-function manner.     

Ca2+ channel modulation by 8-bromocyclic AMP in cultured heart cells

Modulation of ion channels is of increasing interest as it is an important step in the regulation of cellular functions. We have analysed the effect of 8-bromocyclic AMP on Ca2+ channels in cultured cardiac cells by the patch-clamp method and report here that there was a large increase in the probability of opening of the channels. On the basis of a recently proposed kinetic reaction scheme we suggest that cyclic AMP-dependent phosphorylation of Ca2+ channels primarily promotes the forward rate constants which lead to the open state of a Ca2+ channel during depolarization.     

Cdk5 targets active Src for ubiquitin-dependent degradation by phosphorylating Src(S75)

The non-receptor tyrosine kinase Src is a critical regulator of cytoskeletal contraction, cell adhesion, and migration. In normal cells, Src activity is stringently controlled by Csk-dependent phosphorylation of Src(Y530), and by Cullin-5-dependent ubiquitinylation, which affects active Src(pY419) exclusively, leading to its degradation by the proteosome. Previous work has shown that Src activity is also limited by Cdk5, a proline-directed kinase, which has been shown to phosphorylate Src(S75). Here we show that this phosphorylation promotes the ubiquitin-dependent degradation of Src, thus restricting the availability of active Src. We demonstrate that Src(S75) phosphorylation occurs in vivo in epithelial cells, and like ubiquitinylation, is associated only with active Src. Preventing Cdk5-dependent phosphorylation of Src(S75), by site-specific mutation of S75 or by Cdk5 inhibition or suppression, increases Src(Y419) phosphorylation and kinase activity, resulting in Src-dependent cytoskeletal changes. In transfected cells, ubiquitinylation of Src(S75A) is about 35% that of wild-type Src-V5, and its half-life is approximately 2.5-fold greater. Cdk5 suppression leads to a comparable decrease in the ubiquitinylation of endogenous Src and a similar increase in Src stability. Together, these findings demonstrate that Cdk5-dependent phosphorylation of Src(S75) is a physiologically significant mechanism of regulating intracellular Src activity.     

Identification of a bacterial inhibitor against g-type lysozyme

Lysozymes are antibacterial effectors of the innate immune system in animals that hydrolyze peptidoglycan. Bacteria have evolved protective mechanisms that contribute to lysozyme tolerance such as the production of lysozyme inhibitors, but only inhibitors of chicken (c-) and invertebrate (i-) type lysozyme have been identified. We here report the discovery of a novel Escherichia coli inhibitor specific for goose (g-) type lysozymes, which we designate PliG (periplasmic lysozyme inhibitor of g-type lysozyme). Although it does not inhibit c- or i-type lysozymes, PliG shares a structural sequence motif with the previously described PliI and MliC/PliC lysozyme inhibitor families, suggesting a common ancestry and mode of action. Deletion of pliG increased the sensitivity of E. coli to g-type lysozyme. The existence of inhibitors against all major types of animal lysozyme and their contribution to lysozyme tolerance suggest that lysozyme inhibitors may play a role in bacterial interactions with animal hosts.