Transcriptome and proteome dynamics of cervical remodeling in the mouse during pregnancy

Abstract During gestation, the female reproductive tract must maintain pregnancy while concurrently preparing for parturition. Here, we explore the transitions in gene expression and protein turnover (fractional synthesis rates [FSR]) by which the cervix implements a transition from rigid to compliant. Shifts in gene transcription to achieve immune tolerance and alter epithelial cell programs begin in early pregnancy. Subsequently, in mid-to-late pregnancy transcriptional programs emerge that promote structural reorganization of the extracellular matrix (ECM). Stable isotope labeling revealed a striking slowdown of overall FSRs across the proteome on gestation day 6 that reverses in mid-to-late pregnancy. An exception was soluble fibrillar collagens and proteins of collagen assembly, which exhibit high turnover in non-pregnant cervix compared to other tissues and FSRs that continue throughout pregnancy. This finding provides a mechanism to explain how cross-linked collagen is replaced by newly synthesized, less-cross-linked collagens, which allows increased tissue compliance during parturition. The rapid transition requires a reservoir of newly synthesized, less cross-linked collagens, which is assured by the high FSR of soluble collagens in the cervix. These findings suggest a previously unrecognized form of “metabolic flexibility” for ECM in the cervix that underlies rapid transformation in compliance to allow parturition.

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Revealing mechanisms of mating plug function under sexual selection

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1920526117 ◽

2020 ◽

Vol 117 (44) ◽

pp. 27465-27473

Author(s):

Paula Stockley ◽

Catarina Franco ◽

Amy J. Claydon ◽

Amanda Davidson ◽

Dean E. Hammond ◽

...

Keyword(s):

Sexual Selection ◽

Natural Variation ◽

Reproductive Tract ◽

Isotope Labeling ◽

Fertilization Success ◽

Female Reproductive Tract ◽

Myodes Glareolus ◽

Accessory Glands ◽

Direct Competition

Mating plugs are produced by many sexually reproducing animals and are hypothesized to promote male fertilization success under promiscuous mating. However, tests of this hypothesis have been constrained by an inability to discriminate ejaculates of different males in direct competition. Here, we use stable isotope labeling in vivo and proteomics to achieve this in a promiscuous rodent,Myodes glareolus. We show that, although the first male’s plug is usually dislodged, it can be retained throughout the second male’s copulation. Retained plugs did not completely block rival sperm but did significantly limit their numbers. Differences in the number of each male’s sperm progressing through the female reproductive tract were also explained by natural variation in the size of mating plugs and reproductive accessory glands from which major plug proteins originate. Relative sperm numbers in turn predicted the relative fertilization success of rival males. Our application of stable isotopes to label ejaculates resolves a longstanding debate by revealing how rodent mating plugs promote fertilization success under competitive conditions. This approach opens new opportunities to reveal cryptic mechanisms of postcopulatory sexual selection among diverse animal taxa.

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Reproduction in natural populations of the Australian ringtail possum, Pseudocheirus peregrinus (Marsupialia: Phalangeridae) in Victora.

Australian Journal of Zoology ◽

10.1071/zo9650383 ◽

1965 ◽

Vol 13 (3) ◽

pp. 383 ◽

Cited By ~ 23

Author(s):

RL Hughes ◽

JA Thomson ◽

WH Owen

Keyword(s):

Breeding Season ◽

Reproductive Tract ◽

Natural Populations ◽

Late Pregnancy ◽

Female Reproductive Tract ◽

Foetal Head ◽

Uterine Mucosa ◽

Pseudocheirus Peregrinus ◽

Marsupial Species ◽

Ventral Area

Reproductive data from 83 female and 34 male ringtail possums, living in natural populations, have been accumulated over a 3-yr period (March 1960-May 1963). Reproductive tracts from 75 females killed during this period have been examined. Pseudocheirus is polyoestrous and breeds between the latter half of April and the end of November. The whole female reproductive tract and, in the male, the testes then undergo involution until the next breeding season. The majority of conceptions occur early in the breeding season when one to three eggs are shed and fertilized at one time. Supra-ovulation was not observed and the reproductive wastage was very low during pouch life. The mean litter size was two. It is exceptional for females to conceive a second time in one breeding season. Of the four teats, the posterior pair were selected by 85 % of the new-born young. The frequency of lactation in each posterior teat was approximately equal in 58 females. In advanced pregnancy (foetal head length, 6.5 mm) the subepithelial blood net of the uterine mucosa was more highly developed adjacent to a dorsal and ventral area of the vascular portion of the foetal yolksac. In these regions dense foetal blood vessel nets were formed by intense localized branching of the foetal vitelline veins on the yolksac. The foetal membrane, the allantois, was surprisingly large (8 mm diam.), and although not attached to the chorion possessed a conspicuous blood net in its base. An account of the histology of the ovary and reproductive tract includes the following reproductive conditions : juvenile, oestrus, early and late pregnancy, lactation, and anoestrus. Reproduction in Pseudocheirus is briefly compared to that of other marsupial species.

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Effect of Contraceptive Steroids on the Endometrium of Guinea Pig: SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080766 ◽

1977 ◽

Vol 35 ◽

pp. 668-669

Author(s):

Mai M. Said ◽

Ramesh K. Nayak ◽

Randall E. McCoy

Keyword(s):

Guinea Pig ◽

Reproductive Tract ◽

Three Dimensional ◽

Female Reproductive Tract ◽

Human Female ◽

Surface Ultrastructure ◽

Transmission Electron ◽

Sem Study ◽

Uterine Mucosa ◽

Group 1

Burgos and Wislocki described changes in the mucosa of the guinea pig uterus, cervix and vagina during the estrous cycle investigated by transmission electron microscopy. More recently, Moghissi and Reame reported the effects of progestational agents on the human female reproductive tract. They found drooping and shortening of cilia in norgestrel and norethindrone- treated endometria. To the best of our knowledge, no studies concerning the effects of mestranol and norethindrone given concurrently on the three-dimensional surface features on the uterine mucosa of the guinea pig have been reported. The purpose of this study was to determine the effect of mestranol and norethindrone on surface ultrastructure of guinea pig uterus by SEM.Seventy eight animals were used in this study. They were allocated into two groups. Group 1 (20 animals) was injected intramuscularly 0.1 ml vegetable oil and served as controls.

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Surface ultrastructure of danazol treated rat endometrium: A SEM study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010007641x ◽

1983 ◽

Vol 41 ◽

pp. 556-557

Author(s):

R.P. Apkarian ◽

J.S. Sanfilippo

Keyword(s):

Cross Sections ◽

Reproductive Tract ◽

Preliminary Investigation ◽

Breast Disease ◽

Distal Segment ◽

Uterine Horn ◽

Female Reproductive Tract ◽

Ultrastructural Changes ◽

Cycle Phase ◽

Sprague Dawley

The synthetic androgen danazol, is an isoxazol derivative of ethisterone. It is utilized in the treatment of endometriosis, fibrocystic breast disease, and has a potential use as a contraceptive. A study was designed to evaluate the ultrastructural changes associated with danazol therapy in a rat model. The preliminary investigation of the distal segment of the rat uterine horn was undertaken as part of a larger study intended to elucidate the effects of danazol on the female reproductive tract.Cross-sections (2-3 mm in length) of the distal segment of the uterine horn from sixteen Sprague-Dawley rats were prepared for SEM. Ten rats in estrus served as controls and six danazol treated rats were noted to have alterations of the estrus cycle i.e. a lag in cycle phase or noncycling patterns. Specimens were fixed in 3% glutaraldehyde in 0.05M phosphate buffer containing CaCl2 at pH 7.0-7.4 and chilled to 4°C. After a brief wash in distilled water, specimens were passed through a graded series of ethanol, critical point dryed in CO2 from absolute ethanol, and coated with 6nm Au. Observations were made with an IS1-40 SEM operated at 15kV.

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The application of electron microscopy to diagnosis in gynecologic neoplasms and tumor-like conditions

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100110787 ◽

1984 ◽

Vol 42 ◽

pp. 102-105

Author(s):

Lawrence M. Roth

Keyword(s):

Electron Microscopy ◽

Reproductive Tract ◽

Malignant Tumors ◽

Frozen Section ◽

Cost Effective ◽

Female Reproductive Tract ◽

Ultrastructural Examination ◽

Specific Diagnosis ◽

Potential Value ◽

Gynecologic Neoplasms

The female reproductive tract may be the site of a wide variety of benign and malignant tumors, as well as non-neoplastic tumor-like conditions, most of which can be diagnosed by light microscopic examination including special stains and more recently immunoperoxidase techniques. Nevertheless there are situations where ultrastructural examination can contribute substantially to an accurate and specific diagnosis. It is my opinion that electron microscopy can be of greatest benefit and is most cost effective when applied in conjunction with other methodologies. Thus, I have developed an approach which has proved useful for me and may have benefit for others. In cases where it is deemed of potential value, glutaraldehyde-fixed material is obtained at the time of frozen section or otherwise at operation. Coordination with the gynecologic oncologist is required in the latter situation. This material is processed and blocked and is available if a future need arises.

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