TY  - JOUR
A1  - Rodríguez-Mari, Adriana
A1  - Wilson, Catherine
A1  - Titus, Tom A.
A1  - Canestro, Cristian
A1  - BreMiller, Ruth A.
A1  - Yan, Yi-Lin
A1  - Nanda, Indrajit
A1  - Johnston, Adam
A1  - Kanki, John P.
A1  - Gray, Erin M.
A1  - He, Xinjun
A1  - Spitsbergen, Jan
A1  - Schindler, Detlev
A1  - Postlethwait, John H.
T1  - Roles of brca2 (fancd1) in Oocyte Nuclear Architecture, Gametogenesis, Gonad Tumors, and Genome Stability in Zebrafish
JF  - PLoS Genetics
N2  - Functional near-infrared spectroscopy (fNIRS) is an established optical neuroimaging method for measuring functional hemodynamic responses to infer neural activation. However, the impact of individual anatomy on the sensitivity of fNIRS measuring hemodynamics within cortical gray matter is still unknown. By means of Monte Carlo simulations and structural MRI of 23 healthy subjects (mean age: (25.0 +/- 2.8) years), we characterized the individual distribution of tissue-specific NIR-light absorption underneath 24 prefrontal fNIRS channels. We, thereby, investigated the impact of scalp-cortex distance (SCD), frontal sinus volume as well as sulcal morphology on gray matter volumes (V(gray)) traversed by NIR-light, i.e. anatomy-dependent fNIRS sensitivity. The NIR-light absorption between optodes was distributed describing a rotational ellipsoid with a mean penetration depth of (23.6 +/- 0.7) mm considering the deepest 5% of light. Of the detected photon packages scalp and bone absorbed (96.4 +/- 9: 7)% and V(gray) absorbed (3.1 +/- 1.8)% of the energy. The mean V(gray) volume (1.1 +/- 0.4)cm(3) was negatively correlated (r = - .76) with the SCD and frontal sinus volume (r = - .57) and was reduced by 41.5% in subjects with relatively large compared to small frontal sinus. Head circumference was significantly positively correlated with the mean SCD (r = .46) and the traversed frontal sinus volume (r = .43). Sulcal morphology had no significant impact on V(gray). Our findings suggest to consider individual SCD and frontal sinus volume as anatomical factors impacting fNIRS sensitivity. Head circumference may represent a practical measure to partly control for these sources of error variance.
KW  - oocytes
KW  - zebrafish
KW  - genetic causes of cancer
KW  - testes
KW  - apoptosis
KW  - gonads
KW  - sperm
KW  - embryos
Y1  - 2011
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-142285
VL  - 7
IS  - 3
ER  - 
TY  - JOUR
A1  - Alsheimer, Manfred
A1  - Link, Jana
A1  - Jahn, Daniel
A1  - Schmitt, Johannes
A1  - Göb, Eva
A1  - Baar, Johannes
A1  - Ortega, Sagrario
A1  - Benavente, Ricardo
T1  - The Meiotic Nuclear Lamina Regulates Chromosome Dynamics and Promotes Efficient Homologous Recombination in the Mouse
JF  - PLoS Genetics
N2  - The nuclear lamina is the structural scaffold of the nuclear envelope and is well known for its central role in nuclear organization and maintaining nuclear stability and shape. In the past, a number of severe human disorders have been identified to be associated with mutations in lamins. Extensive research on this topic has provided novel important clues about nuclear lamina function. These studies have contributed to the knowledge that the lamina constitutes a complex multifunctional platform combining both structural and regulatory functions. Here, we report that, in addition to the previously demonstrated significance for somatic cell differentiation and maintenance, the nuclear lamina is also an essential determinant for germ cell development. Both male and female mice lacking the short meiosis-specific A-type lamin C2 have a severely defective meiosis, which at least in the male results in infertility. Detailed analysis revealed that lamin C2 is required for telomere-driven dynamic repositioning of meiotic chromosomes. Loss of lamin C2 affects precise synapsis of the homologs and interferes with meiotic double-strand break repair. Taken together, our data explain how the nuclear lamina contributes to meiotic chromosome behaviour and accurate genome haploidization on a mechanistic level.
KW  - homologous chromosomes
KW  - homologous recombination
KW  - lamins
KW  - Oocytes
KW  - spermatocytes
KW  - synapsis
KW  - telomeres
KW  - testes
Y1  - 2013
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-96285
ER  -