Examining Head-shape Differences and Ecology in Morphologically Similar Salamanders at Their Zone of Contact

Copeia ◽  
2016 ◽  
Vol 104 (1) ◽  
pp. 233-242 ◽  
Author(s):  
Jennifer Deitloff ◽  
Claire Floyd ◽  
Sean P. Graham
Keyword(s):  
Head Shape

3D-Measuring for Head Shape Covering Hair

2011 ◽  
Vol 131 (12) ◽  
pp. 2082-2088 ◽  
Author(s):  
Tsukasa Kato ◽  
Koosuke Hattori ◽  
Takuya Nomura ◽  
Ryo Taguchi ◽  
Masahiro Hoguro ◽  
...  
Keyword(s):  
Head Shape

scholarly journals Variation in pleiotropic hub gene expression is associated with interspecific differences in head shape and eye size in Drosophila

2021 ◽  
Author(s):  
Elisa Buchberger ◽  
Anıl Bilen ◽  
Sanem Ayaz ◽  
David Salamanca ◽  
Cristina Matas de las Heras ◽  
...  
Keyword(s):  
Natural Variation ◽  
Compound Eye ◽  
Genetic Manipulation ◽  
Morphological Evolution ◽  
Morphological Diversity ◽  
Network Evolution ◽  
Head Shape ◽  
Eye Size ◽  
Recurrent Mutations ◽  
Repeated Evolution

Abstract Revealing the mechanisms underlying the breath-taking morphological diversity observed in nature is a major challenge in Biology. It has been established that recurrent mutations in hotspot genes cause the repeated evolution of morphological traits, such as body pigmentation or the gain and loss of structures. To date, however, it remains elusive whether hotspot genes contribute to natural variation in the size and shape of organs. Since natural variation in head morphology is pervasive in Drosophila, we studied the molecular and developmental basis of differences in compound eye size and head shape in two closely related Drosophila species. We show differences in the progression of retinal differentiation between species and we applied comparative transcriptomics and chromatin accessibility data to identify the GATA transcription factor Pannier (Pnr) as central factor associated with these differences. Although the genetic manipulation of Pnr affected multiple aspects of dorsal head development, the effect of natural variation is restricted to a subset of the phenotypic space. We present data suggesting that this developmental constraint is caused by the co-evolution of expression of pnr and its co-factor u-shaped (ush). We propose that natural variation in expression or function of highly connected developmental regulators with pleiotropic functions is a major driver for morphological evolution and we discuss implications on gene regulatory network evolution. In comparison to previous findings, our data strongly suggests that evolutionary hotspots are not the only contributors to the repeated evolution of eye size and head shape in Drosophila.

Radiographic Measurements of the Affected and Unaffected Feet in Patients with Unilateral Hallux Limitus

2016 ◽  
Vol 106 (3) ◽  
pp. 172-181
Author(s):  
Andrew F. Knox ◽  
Alan R. Bryant
Keyword(s):  
Metatarsal Head ◽  
Radiographic Evaluation ◽  
Head Shape ◽  
Intrinsic Factors ◽  
Hallux Limitus ◽  
First Metatarsal ◽  
Radiographic Measurements ◽  
Angle Data ◽  
Significant Difference ◽  
First Ray

Background: Controversy exists regarding the structural and functional causes of hallux limitus, including metatarsus primus elevatus, a long first metatarsal, first-ray hypermobility, the shape of the first metatarsal head, and the presence of hallux interphalangeus. Some articles have reported on the radiographic evaluation of these measurements in feet affected by hallux limitus, but no study has directly compared the affected and unaffected feet in patients with unilateral hallux limitus. This case-control pilot study aimed to establish whether any such differences exist. Methods: Dorsoplantar and lateral weightbearing radiographs of both feet in 30 patients with unilateral hallux limitus were assessed for grade of disease, lateral intermetatarsal angle, metatarsal protrusion distance, plantar gapping at the first metatarsocuneiform joint, metatarsal head shape, and hallux abductus interphalangeus angle. Data analysis was performed using a statistical software program. Results: Mean radiographic measurements for affected and unaffected feet demonstrated that metatarsus primus elevatus, a short first metatarsal, first-ray hypermobility, a flat metatarsal head shape, and hallux interphalangeus were prevalent in both feet. There was no statistically significant difference between feet for any of the radiographic parameters measured (Mann-Whitney U tests, independent-samples t tests, and Pearson χ2 tests: P > .05). Conclusions: No significant differences exist in the presence of the structural risk factors examined between affected and unaffected feet in patients with unilateral hallux limitus. The influence of other intrinsic factors, including footedness and family history, should be investigated further.

Disorders of Head Shape and Size

2020 ◽  
pp. 957-999
Author(s):  
Essam A. Elgamal ◽  
Mustafa A. M. Salih
Keyword(s):  
Head Shape ◽  
Shape And Size

A mutation study of sperm head shape and motility in the mouse: lessons for the clinic

Andrology ◽  
2014 ◽  
Vol 3 (2) ◽  
pp. 174-202 ◽  
Author(s):  
P. de Boer ◽  
M. de Vries ◽  
L. Ramos
Keyword(s):  
Sperm Head ◽  
Head Shape

scholarly journals Loss of Profilin3 Impairs Spermiogenesis by Affecting Acrosome Biogenesis, Autophagy, Manchette Development and Mitochondrial Organization

2021 ◽  
Vol 9 ◽  
Author(s):  
Naila Umer ◽  
Lena Arévalo ◽  
Sharang Phadke ◽  
Keerthika Lohanadan ◽  
Gregor Kirfel ◽  
...  
Keyword(s):  
Actin Polymerization ◽  
Regulatory Proteins ◽  
Autophagic Flux ◽  
Nuclear Fraction ◽  
Rna Seq ◽  
Head Shape ◽  
Male Factor ◽  
Protein Levels ◽  
Acrosome Formation ◽  
Actin Regulatory Proteins

Profilins (PFNs) are key regulatory proteins for the actin polymerization in cells and are encoded in mouse and humans by four Pfn genes. PFNs are involved in cell mobility, cell growth, neurogenesis, and metastasis of tumor cells. The testes-specific PFN3 is localized in the acroplaxome–manchette complex of developing spermatozoa. We demonstrate that PFN3 further localizes in the Golgi complex and proacrosomal vesicles during spermiogenesis, suggesting a role in vesicle transport for acrosome formation. Using CRISPR/Cas9 genome editing, we generated mice deficient for Pfn3. Pfn3–/– males are subfertile, displaying a type II globozoospermia. We revealed that Pfn3–/– sperm display abnormal manchette development leading to an amorphous sperm head shape. Additionally, Pfn3–/– sperm showed reduced sperm motility resulting from flagellum deformities. We show that acrosome biogenesis is impaired starting from the Golgi phase, and mature sperm seems to suffer from a cytoplasm removal defect. An RNA-seq analysis revealed an upregulation of Trim27 and downregulation of Atg2a. As a consequence, mTOR was activated and AMPK was suppressed, resulting in the inhibition of autophagy. This dysregulation of AMPK/mTOR affected the autophagic flux, which is hallmarked by LC3B accumulation and increased SQSTM1 protein levels. Autophagy is involved in proacrosomal vesicle fusion and transport to form the acrosome. We conclude that this disruption leads to the observed malformation of the acrosome. TRIM27 is associated with PFN3 as determined by co-immunoprecipitation from testis extracts. Further, actin-related protein ARPM1 was absent in the nuclear fraction of Pfn3–/– testes and sperm. This suggests that lack of PFN3 leads to destabilization of the PFN3–ARPM1 complex, resulting in the degradation of ARPM1. Interestingly, in the Pfn3–/– testes, we detected increased protein levels of essential actin regulatory proteins, cofilin-1 (CFL1), cofilin-2 (CFL2), and actin depolymerizing factor (ADF). Taken together, our results reveal the importance for PFN3 in male fertility and implicate this protein as a candidate for male factor infertility in humans.

scholarly journals Earliest-known intentionally deformed human cranial fossil from Asia and the initiation of hereditary hierarchy in the early Holocene

2019 ◽  
Author(s):  
Xijun Ni ◽  
Qiang Li ◽  
Thomas A. Stidham ◽  
Yangheshan Yang ◽  
Qiang Ji ◽  
...  
Keyword(s):  
Cultural Practice ◽  
Northeastern China ◽  
Early Holocene ◽  
Population Increase ◽  
Complex Societies ◽  
Head Shape ◽  
Northeastern Asia ◽  
Radiocarbon Age ◽  
The World ◽  
Terminal Pleistocene

AbstractHereditary hierarchy is one of the major features of complex societies. Without a written record, prehistoric evidence for hereditary hierarchy is rare. Intentional cranial deformation (ICD) is a cross-generational cultural practice that embodies social identity and culture beliefs in adults through the behavior of altering infant head shape. Therefore, ICD is usually regarded as an archeological clue for the occurrence of hereditary hierarchy. With a calibrated radiocarbon age of 11245-11200 years BP, a fossil skull of an adult male displaying ICD discovered in Northeastern China is among the oldest-known ICD practices in the world. Along with the other earliest global occurrences of ICD, this discovery points to the early initiation of complex societies among the non-agricultural local societies in Northeastern Asia in the early Holocene. A population increase among previously more isolated terminal Pleistocene/early Holocene hunter-gatherer groups likely increased their interactions, possibly fueling the formation of the first complex societies.

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