29 research outputs found
Recessive <i>HYDIN</i> mutations cause primary ciliary dyskinesia without randomization of left-right body asymmetry
Primary ciliary dyskinesia (PCD) is a genetically heterogeneous
recessive disorder characterized by defective cilia and flagella
motility. Chronic destructive-airway disease is caused by
abnormal respiratory-tract mucociliary clearance. Abnormal
propulsion of sperm flagella contributes to male infertility.
Genetic defects in most individuals affected by PCD cause
randomization of left-right body asymmetry; approximately half
show situs inversus or situs ambiguous. Almost 70 years after
the hy3 mouse possessing Hydin mutations was described as a
recessive hydrocephalus model, we report HYDIN mutations in PCD-
affected persons without hydrocephalus. By homozygosity mapping,
we identified a PCD-associated locus, chromosomal region 16q21-
q23, which contains HYDIN. However, a nearly identical 360 kb
paralogous segment (HYDIN2) in chromosomal region 1q21.1
complicated mutational analysis. In three affected German
siblings linked to HYDIN, we identified homozygous c.3985G>T
mutations that affect an evolutionary conserved splice acceptor
site and that subsequently cause aberrantly spliced transcripts
predicting premature protein termination in respiratory cells.
Parallel whole-exome sequencing identified a homozygous nonsense
HYDIN mutation, c.922A>T (p.Lys307( *)), in six individuals from
three Faroe Island PCD-affected families that all carried an 8.8
Mb shared haplotype across HYDIN, indicating an ancestral
founder mutation in this isolated population. We demonstrate by
electron microscopy tomography that, consistent with the effects
of loss-of-function mutations, HYDIN mutant respiratory cilia
lack the C2b projection of the central pair (CP) apparatus;
similar findings were reported in Hydin-deficient Chlamydomonas
and mice. High-speed videomicroscopy demonstrated markedly
reduced beating amplitudes of respiratory cilia and stiff sperm
flagella. Like the hy3 mouse model, all nine PCD-affected
persons had normal body composition because nodal cilia function
is apparently not dependent on the function of the CP
apparatus
Mapping human dispersals into the Horn of Africa from Arabian Ice Age refugia using mitogenomes
Rare mitochondrial lineages with relict distributions can sometimes be disproportionately informative about deep events in human prehistory. We have studied one such lineage, haplogroup R0a, which uniquely is most frequent in Arabia and the Horn of Africa, but is distributed much more widely, from Europe to India. We conclude that: (1) the lineage ancestral to R0a is more ancient than previously thought, with a relict distribution across the Mediterranean/Southwest Asia; (2) R0a has a much deeper presence in Arabia than previously thought, highlighting the role of at least one Pleistocene glacial refugium, perhaps on the Red Sea plains; (3) the main episode of dispersal into Eastern Africa, at least concerning maternal lineages, was at the end of the Late Glacial, due to major expansions from one or more refugia in Arabia; (4) there was likely a minor Late Glacial/early postglacial dispersal from Arabia through the Levant and into Europe, possibly alongside other lineages from a Levantine refugium; and (5) the presence of R0a in Southwest Arabia in the Holocene at the nexus of a trading network that developed after ~3 ka between Africa and the Indian Ocean led to some gene flow even further afield, into Iran, Pakistan and India
Furin-Mediated Sequential Delivery of Anticancer Cytokine and Small-Molecule Drug Shuttled by Graphene
A cellular protease (furin)-mediated graphene-based nanosystem is developed for co-delivery of a membrane-associated cytokine (tumor-necrosis-factor-related apoptosis-inducing ligand, TRAIL) and an intracellular-acting small-molecule drug (Doxorubicin, DOX). TRAIL and DOX can be sequentially released toward the plasma membrane and nucleus, respectively
Origin and spread of human mitochondrial DNA haplogroup U7
Human mitochondrial DNA haplogroup U is among the initial maternal founders in Southwest Asia and Europe and one that best indicates matrilineal genetic continuity between late Pleistocene hunter-gatherer groups and present-day populations of Europe. While most haplogroup U subclades are older than 30 thousand years, the comparatively recent coalescence time of the extant variation of haplogroup U7 (~16–19 thousand years ago) suggests that its current distribution is the consequence of more recent dispersal events, despite its wide geographical range across Europe, the Near East and South Asia. Here we report 267 new U7 mitogenomes that – analysed alongside 100 published ones – enable us to discern at least two distinct temporal phases of dispersal, both of which most likely emanated from the Near East. The earlier one began prior to the Holocene (~11.5 thousand years ago) towards South Asia, while the later dispersal took place more recently towards Mediterranean Europe during the Neolithic (~8 thousand years ago). These findings imply that the carriers of haplogroup U7 spread to South Asia and Europe before the suggested Bronze Age expansion of Indo-European languages from the Pontic-Caspian Steppe region
Early holocenic and historic mtDNA african signatures in the iberian peninsula: The andalusian region as a paradigm
Determining the timing, identity and direction of migrations in the Mediterranean Basin, the role of "migratory routes" in and among regions of Africa, Europe and Asia, and the effects of sex-specific behaviors of population movements have important implications for our understanding of the present human genetic diversity. A crucial component of the Mediterranean world is its westernmost region. Clear features of transcontinental ancient contacts between North African and Iberian populations surrounding the maritime region of Gibraltar Strait have been identified from archeological data. The attempt to discern origin and dates of migration between close geographically related regions has been a challenge in the field of uniparental-based population genetics. Mitochondrial DNA (mtDNA) studies have been focused on surveying the H1, H3 and V lineages when trying to ascertain north-south migrations, and U6 and L in the opposite direction, assuming that those lineages are good proxies for the ancestry of each side of the Mediterranean. To this end, in the present work we have screened entire mtDNA sequences belonging to U6, M1 and L haplogroups in Andalusians--from Huelva and Granada provinces--and Moroccan Berbers. We present here pioneer data and interpretations on the role of NW Africa and the Iberian Peninsula regarding the time of origin, number of founders and expansion directions of these specific markers. The estimated entrance of the North African U6 lineages into Iberia at 10 ky correlates well with other L African clades, indicating that U6 and some L lineages moved together from Africa to Iberia in the Early Holocene. Still, founder analysis highlights that the high sharing of lineages between North Africa and Iberia results from a complex process continued through time, impairing simplistic interpretations. In particular, our work supports the existence of an ancient, frequently denied, bridge connecting the Maghreb and Andalusia.Financial support was provided by the Spanish Ministry of Competitiveness through Research Project CGL2010-15191/BOS granted to RC and International Mobility Program Acciones Integradas Hispano-Portuguesas (PRI-AIBPT-2011-1004) granted to RC (Spain) and LP (Portugal) (http://www.mineco.gob.es/portal/site/mineco/idi). The E.C. Sixth Framework Programme under Contract n° ERAS-CT-2003-980409 (EUROCORES project of the European Science Foundation) also provided financial support to JMD for North African population research. CLH has a predoctoral fellowship granted by Complutense University. PS is supported by FCT Investigator Programme (IF/01641/2013). IPATIMUP (https://www.ipatimup.pt/) integrates the Instituto the Investigação em Saúde (i3S) Research Unit, which is partially supported by FCT, the Portuguese Foundation for Science and Technology. IPATIMUP is funded by FEDER funds through the Operational Programme for Competitiveness Factors - COMPETE and National Funds through the FCT - under the project PEst-C/SAU/LA0003/2013. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript