Functional morphology and evolution of aspiration breathing in tetrapods

Brainerd, Elizabeth L.; Owerkowicz, Tomasz

doi:10.1016/j.resp.2006.06.003

Cited by 71 publications

(63 citation statements)

References 80 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Morphological variation in the epithelial architecture is well exemplified in the evolutionary distant species (Botella et al, 2007;Brainerd and Owerkowicz, 2006;Delgado et al, 2005;Ichim et al, 2007;Iwasaki, 2002;Mitsiadis et al, 2003). We showed that the oral epithelium-specific enhancer MRCS1 is conserved in birds and reptiles at the almost same level as in mammals, whereas its homolog has not been identified in amphibians and teleost fishes.…”

Section: Evolutionary Diversification Of the Enhancersmentioning

confidence: 83%

A cluster of three long-range enhancers directs regionalShhexpression in the epithelial linings

et al. 2009

View full text Add to dashboard Cite

The sonic hedgehog (Shh) pathway plays indispensable roles in the morphogenesis of mouse epithelial linings of the oral cavity and respiratory and digestive tubes. However, no enhancers that regulate regional Shh expression within the epithelial linings have been identified so far. In this study, comparison of genomic sequences across mammalian species and teleost fishes revealed three novel conserved non-coding sequences (CNCSs) that cluster in a region 600 to 900 kb upstream of the transcriptional start site of the mouse Shh gene. These CNCSs drive regional transgenic lacZ reporter expression in the epithelial lining of the oral cavity, pharynx, lung and gut. Together, these enhancers recapitulate the endogenous Shh expression domain within the major epithelial linings. Notably, genomic arrangement of the three CNCSs shows co-linearity that mirrors the order of the epithelial expression domains along the anteroposterior body axis. The results suggest that the three CNCSs are epithelial lining-specific long-range Shh enhancers, and that their actions partition the continuous epithelial linings into three domains: ectoderm-derived oral cavity, endoderm-derived pharynx, and respiratory and digestive tubes of the mouse. Targeted deletion of the pharyngeal epithelium specific CNCS results in loss of endogenous Shh expression in the pharynx and postnatal lethality owing to hypoplasia of the soft palate, epiglottis and arytenoid. Thus, this long-range enhancer is indispensable for morphogenesis of the pharyngeal apparatus.

show abstract

Section: Evolutionary Diversification Of the Enhancersmentioning

confidence: 83%

A cluster of three long-range enhancers directs regionalShhexpression in the epithelial linings

et al. 2009

View full text Add to dashboard Cite

show abstract

“…The ribs and intercostal muscles form a set of skeletal lever systems that convert intercostal muscle shortening into lateral and cranial motion of the ribs. This costal aspiration system appears to be the primitive ventilation mechanism for amniotes (Brainerd and Owerkowicz, 2006). Accessory diaphragm-like arrangements have evolved independently in mammals, turtles and crocodilians, but in all extant amniotes except turtles, rib motions contribute to lung ventilation, suggesting that costal aspiration is primitive for amniotes (Brainerd, 2015;Brainerd and Owerkowicz, 2006).…”

Section: Introductionmentioning

confidence: 99%

XROMM analysis of rib kinematics during lung ventilation in the green iguana, Iguana iguana

Brainerd

Moritz

Ritter

2015

Journal of Experimental Biology

Self Cite

View full text Add to dashboard Cite

The three-dimensional rotations of ribs during breathing are typically described as bucket-handle rotation about a dorsoventrally oriented axis, pump-handle rotation about a mediolateral axis, and caliper rotation about a rostrocaudal axis. In amniotes with double-headed ribs, rib motion is constrained primarily to one degree-of-freedom (DOF) rotation about an axis connecting the two rib articulations. However, in Squamata, the ribs are single headed and the hemispherical costovertebral joints permit rotations with three DOF. In this study, we used X-ray reconstruction of moving morphology (XROMM ) to quantify rib rotation during deep breathing in four green iguanas. We found that rib rotation was strongly dominated by buckethandle rotation, thus exhibiting nearly hinge-like motion, despite the potential for more complex motions. The vertebral and sternal segments of each rib did not deform measurably during breathing, but they did move relative to each other at a thin, cartilaginous intracostal joint. While standing still and breathing deeply, four individual iguanas showed variability in their rib postures, with two breathing around a highly inflated posture, and two breathing around a posture with the ribs folded halfway back. Bucket-handle rotations showed clear rostrocaudal gradients, with rotation increasing from the third cervical to the first or second dorsal rib, and then decreasing again caudally, a pattern that is consistent with the intercostal muscles in the rostral intercostal spaces being the primary drivers of inspiration. The constrained, primarily bucket-handle rotations observed here during breathing do not help to explain the evolution of permissive, hemispherical costovertebral joints in squamates from the more constrained, double-headed rib articulations of other amniotes.

show abstract

“…This was achieved by different strategies within the different vertebrate classes. Early tetrapods and amphibians ventilate their lungs by a buccal pump (Brainerd and Owerkowicz, 2006). In higher vertebrates ventilation occurs by a costal pump (Roux, 2002) where the movement of the ribs ensures aspiration of air.…”

Section: Air Breathing and Pulmonary Ion Transportmentioning

confidence: 99%

Lung Diseases - Selected State of the Art Reviews

Irusen¹

2012

View full text Add to dashboard Cite

Functional morphology and evolution of aspiration breathing in tetrapods

Cited by 71 publications

References 80 publications

A cluster of three long-range enhancers directs regionalShhexpression in the epithelial linings

A cluster of three long-range enhancers directs regionalShhexpression in the epithelial linings

XROMM analysis of rib kinematics during lung ventilation in the green iguana, Iguana iguana

Lung Diseases - Selected State of the Art Reviews

Contact Info

Product

Resources

About