Effects of testosterone on sequence complexity of polyadenylated RNA from rat seminal vesicle

Effects of Continuous Estradiol Administration by Polydimethylsiloxane and Paraffin Implants on Serum Hormone Levels and Uterine Responses

Since tonic elevated estrogen levels are associated with toxic responses, including tumor promotion, we investigated the effects of continuous estradiol (E2) administration by paraffin or polydimethylsiloxane (Silastic) implants on pituitary and uterine responses. Ovariectomized (OVEX) Sprague-Dawley rats implanted with low-dose (P1) or high-dose (P2) paraffin pellets showed initial high serum E2 levels that decayed rapidly. Silastic implants provided more constant pharmacological serum E2 levels during the 14 days of exposure. Rising serum LH and FSH levels in OVEX controls were suppressed by all E2 implants. Serum prolactin levels, low in OVEX controls, rose after implantation (P1 and P2) but decayed to control values by 14 days. Prolactin induced by pharmacological E2 levels initially rose, dropped by 72 hours, but again rose at later times. Uterine weight, low in OVEX controls, was increased by all implants. At later times, paraffin implants did not appear to release significant amounts of E2. However, removal of P2 implants from donors followed by transfer to new recipients stimulated uterine growth in recipients. All implants increased uterine DNA and RNA levels and the RNA/DNA ratio during the first 24–48 hours, followed by maintenance of elevated values. Poly(A)-containing RNA, isolated by oligo(dT) cellulose chromatography, comprised a constant percentage of RNA at all hormone levels and treatment times, suggesting a coupling of total RNA and poly(A)-containing RNA accumulation. Results are discussed in relation to the carcinogenic properties of estrogens, known to be correlated with continuous exposure to elevated estrogen levels.

Effects of androgens on the transcription of secretory protein genes in rat seminal vesicle

Run-on transcription in isolated nuclei has been used to study the effects of testosterone on gene expression in rat seminal vesicles. General transcriptional rates were increased by about 6-fold with an additional 2- to 3-fold differential stimulation of the genes for secretory proteins IV and V. These transcriptional changes are insufficient to explain overall changes in cellular mRNA levels, indicating that androgens must also have major effects on post-transcriptional processing of RNA transcripts or on mRNA stability. Analysis of nuclear RNA by Northern blotting with intron probes suggests substantial androgen effects on primary transcript processing.

Formation of rat copulatory plug: purified seminal vesicle secretory proteins serve as transglutaminase substrates

An in vitro system has been used to study the role of purified rat seminal vesicle proteins in the formation of the copulatory vaginal plug. Proteins II, IV (or S) and V (or F) were each separately coagulated using the transglutaminase in coagulating gland extracts. In each case the coagulum required Ca2+ ions for its formation and was insoluble in denaturing solvents. In experiments with [3H]lysine, proteins II and S incorporated [3H]lysine into glu-lys dipeptide with similar kinetics. Both the N-terminal and C-terminal glutamine residues of protein S participated in the reaction.

A protein family immunorelated to a sperm-binding protein and its regulation in human semen

In human seminal plasma a family of proteins that is immunologically related to the RSV-IV protein secreted under androgen control from the epithelium of the rat seminal vesicles was detected by a radioimmunoassay. Evidence for the origin of these antigens from human seminal vesicle is presented. Quantitative measurements of this family of proteins were performed in men with low levels of serum testosterone (idiopathic hypogonadotropic hypogonadism) and in individuals having serum testosterone in the normal range of values but carrying sex chromosome aberrations (Klinefelter's syndrome). In the first case we have found a marked decrease in the total amount of the RSV-IV-related proteins. An increase of about 40% in the total amount of these antigens was obtained in these subjects by gonadotropin treatment. A decreased amount of these proteins was also detected in the subjects affected by Klinefelter's syndrome. The possibility that some factor(s) under genetic control is involved, in addition to testosterone, in the regulation of this family of proteins is discussed.

Influence of androgen on translatable renin mRNA in the mouse submandibular gland

In mature outbred Swiss male mice, submandibular gland renin enzyme activity is 4- and 10-fold higher than in glands of prepubescent males and mature females, respectively. Levels of translatable renin mRNA have been studied in mouse submandibular gland during postnatal development and following administration of testosterone. The [35S]methionine-labeled cell-free translation products directed by male glandular mRNA contain a 47 +/- 2kd renin precursor that is not detected in products coded by prepubescent male or female gland mRNA. This cell-free synthesized precursor is detected immunochemically only in the translation products of gland mRNA from males of 33 days or older and from females receiving testosterone administration, a pattern consistent with the measurements of renin enzyme activity. This increase in biologically active renin mRNA is a selective one, since unfractionated male and female mRNAs have similar overall nucleotide sequence complexity corresponding to 1% of mouse single copy DNA. The cDNA transcribed from male gland mRNA reacts 5- and 10-fold faster with the template mRNA than with female or prepubescent male gland mRNA, respectively, which indicates that the male gland contains abundant nucleotide sequences that exist at low concentration in the female or prepubescent male. Selective hybrid arrested translation confirms that the levels of renin mRNA are lower in the glands of prepubescent males than in those of the mature males. These data indicate that the regulation of renin enzymatic activity by androgens is mediated by an increase in the levels of translatable renin mRNA both during postnatal development and after testosterone administration.

Isolation and characterisation of genomic and cDNA clones for an androgen-regulated secretory protein of rat seminal vesicles

Testosterone controls the synthesis of seminal vesicle protein F in male rats by regulating the cellular concentration of its mRNA (mRNAF). Phage lambda recombinants have been isolated containing the complete F gene. In addition plasmids have been constructed containing cDNAF sequences some of which are probably full-length (approximately 700 bp). Detailed restriction mapping shows that the F gene is 1.7 kbp long and contains approximately 1.0 kbp of intervening sequence arranged in at least two introns (420 bp and 600 bp). Part of cDNAF has been sequenced showing that the terminal 125 bp of the 3' untranslated region of mRNAF has substantial (greater than 70%) sequence homology with the 3' end of the mRNA coding for another androgen-dependent seminal vesicle protein (protein S). The cloned F gene has been detected in liver and seminal vesicle DNA along with an homologous but structurally different gene. The hormonal control of mRNAF was examined with cDNAF. A pronounced (approximately 3000-fold) differential response to testosterone was observed.

Isolation and culture of rat seminal vesicle epithelial cells. The use of the secretory protein SVS IV as a functional probe

A method for the isolation and culture of seminal vesicle epithelial cells obtained from control and androgen-primed sexually-immature, uncastrated rats is described. This method allows the establishment of monolayer cultures from aggregates of seminal vesicle epithelial cells isolated after trypsin and collagenase digestion. Phase contrast and transmission electron microscopic methods demonstrate that cell aggregates, after attaching to the substrate, establish within 48 h a colony-like, epithelial-like growth pattern. Immunofluorescent localization studies of SVS IV, an androgen-dependent secretory protein purified from rat seminal vesicle secretion, show that cultured seminal vesicle epithelial cells are immunoreactive. An electrophoretic analysis of [35S]methionine-labeled secretory proteins immunoprecipitated with rabbit anti-SVS IV serum demonstrate that, whereas SVS IV is newly-synthesized and accumulated in the medium of cultured seminal vesicle cells established from androgen primed rats, cultured cells from control rats appear to synthesize and accumulate SVS IV in a precursor form. Results of this work show that seminal vesicle epithelial cells in culture not only retain several structural features representative of the tissue but also serve as a potential system for the study of androgen action.

Effect of androgens on protein synthesis and secretion in various regions of the rat epididymis, as analysed by two-dimensional gel electrophoresis

Protein synthesis and secretion has been quantified in three regions of the rat epididymis (initial segment, caput and cauda) by measuring the rate of incorporation of radioactive methionine by tissue pieces in vitro. The effect of androgens on protein synthesis and secretion was assessed by comparing tissue from untreated animals, castrated animals, and castrated animals receiving injections of testosterone propionate. Androgens caused up to a 2-fold increase in protein synthesis per unit wet weight of tissue. Qualitative effects of androgens on the types of proteins synthesized and secreted were assessed by two-dimensional gel electrophoresis. Androgens induced a differential response in the synthesis of secretory proteins in that some secretory proteins were androgen-regulated whereas others were not. Evidence was also obtained that protein synthesis and secretion in the initial segments of the epididymis responded to some local testicular factor in addition to androgen. The rate of decline in the synthesis of androgen-dependent secretory proteins following castration varied according to the protein. Moreover, the rate of decline in synthesis of the same protein varied markedly in different regions of the epididymis.

Isolation and characterisation of genes for androgen-responsive secretory proteins of rat seminal vesicles

Under the influence of testosterone, rat seminal vesicles synthesise large amounts of a tissue specific protein, S. Recombinant lambda clones have been isolated containing overlapping sequences covering a 27.5 kilo base region of the rat genome within which the gene for protein S is located. Recombinant plasmids bearing cDNA sequences for protein S were constructed in pBR328. One (pcS2) contains a 690 nucleotide insert and is probably full length. Detailed restriction maps of the S-gene are presented and the structure was confirmed by analysis of R-loops and heteroduplexes. The S-gene covers a 2 kbp region of the genome and consists of a 5' intron (490 bp) separating a leading exon (120 bp) containing the 5' untranslated region from a central exon (310 bp) containing most of the coding sequence and part of the 3' untranslated region. A larger intron (1100 bp) lies within the 3' untranslated region. The cloned gene is representative of the native gene but the S gene may be heterogeneous. Using pcS2, the hormonal control of S-specific mRNA was examined and a pronounced differential response to testosterone was observed.

Development of secretory protein synthesis in the seminal vesicles and ventral prostate of the male rat

Functional development of the ventral prostate and seminal vesicles in the male rat has been examined by incubating tissue with [35S] methionine and using specific antisera to detect the synthesis of individual marker proteins. 4 major secretory proteins of the seminal vesicles were chosen along with 4 major prostatic secretory peptides, including 3 which form the prostatic steroid-binding protein. None of the seminal vesicle proteins was synthesised before 25-30 days but all were then induced in parallel to reach adult values by 45-50 days. The 3 peptides of the prostatic steroid-binding protein were synthesised at the earliest age studied (10 days) and were also induced in parallel to maximal levels by 25-30 days. In contrast, the 4th prostatic marker, a glycopeptide, was not synthesised until about 25 days. Treatment of male rats from 3 days of age with testosterone induced precocious development of the seminal vesicles, causing substantial synthesis of marker proteins well before their synthesis would normally have been expected, and also advanced the synthesis of the prostatic 22 K glycopeptide. The results confirm that functional development in the ventral prostate precedes that of the seminal vesicles but that within the ventral prostate there is a considerable difference in the developmental profiles of its secretory proteins.

A microcomputer program for analysis of nucleic acid hybridization data

The study of nucleic acid hybridization is facilitated by computer mediated fitting of theoretical models to experimental data. This paper describes a non-linear curve fitting program, using the 'Patternsearch' algorithm, written in BASIC for the Apple II microcomputer. The advantages and disadvantages of using a microcomputer for local data processing are discussed.

Effects of testosterone on protein synthesis in rat seminal vesicles analysed by two-dimensional gel electrophoresis

Proteins synthesised by seminal vesicles of normal rats were labelled with [35S]methionine and were then separated using two-dimensional gel electrophoresis. Isoelectric focusing or nonequilibrium pH gradient electrophoresis were used in the first dimension followed by polyacrylamide gel electrophoresis under denaturing conditions. Using antiserum to total seminal vesicle secretion and running the immuno-precipitated proteins on two-dimensional gels, secretory proteins were identified and shown to be much more complex than previously thought. Proteins synthesised by seminal vesicles from rats castrated 1-2 weeks before were also labelled with [35S]methionine and separated on two-dimensional gels. Comparison of the two-dimensional protein maps from normal and castrated animals showed that a substantial number of proteins were differentially induced or repressed by testosterone. Of the secretory proteins, some were clearly regulated in a highly differential manner but others appeared to be unaffected by castration. The results are discussed in relation to previous measurements of mRNA sequence complexity and show that previous conclusions derived from using less sophisticated methods are oversimplifications of the response.

Isolation of cells from rat seminal vesicles and epididymis and their use in studying androgen action

Cells isolated enzymically from seminal vesicles and epididymides of normal and castrated rats were shown by electron microscopy to be intact and representative of the tissue. The cells synthesize and secrete tissue-specific proteins. Short-term incorporation of [3H]uridine and [35S]methionine was measured to determine the effects of castration on RNA and protein synthesis. Epididymal cells and tissue incorporated uridine at similar rates which were unaltered by castration. Similarly castration failed to diminish uridine incorporation by seminal vesicle cells and tissue. Therefore, androgens may principally control RNA degradation. A similar situation pertained to methionine incorporation by epididymal cells and tissue so here too control may be via protein degradation. In contrast, castration greatly decreased methionine incorporation by seminal vesicle tissue but not by isolated cells. Isolated cells were more active than in tissue, particularly those from castrated rats, and may be released from stromal-epithelial interactions and controls.

Abundant androgen regulated mRNAs in mouse submandibular gland: cell-free translation of renin precursor mRNA

Submandibular glands of male mice contain at least four abundant mRNAs that occur at low concentrations in glands of females. The male-specific mRNAs code for polypeptides of 48,000, 43,000, 29,000, and 27,000 MW. Androgenic regulation of these mRNAs is illustrated by their apparent absence in glands of castrate males and by their accumulation in glands of females treated with testosterone. Selective hybrid-arrested translation experiments also indicate reduced levels of these male-specific sequences in female gland cytoplasm. The 48,000 MW male-specific polypeptide is reduced in translation products directed by gland mRNA from C57BL10/J mice (variants deficient in salivary renin), suggesting the corresponding mRNA codes for a renin precursor. The identity of this polypeptide is confirmed by immune selection with renin-specific antibody.

Characterization of hormonally regulated secretory proteins from the caput epididymidis of the rabbit

1. The incorporation of [35S]methionine into protein was investigated in tissue minces from different regions of the rabbit epididymis incubated in vitro. Rates of synthesis were in the order: epididymal regions 2-5 greater than region 7 greater than region 6 greater than region 1 greater than region 8 greater than ductus deferens greater than ductuli efferentes. 2. Separation of labelled proteins on polyacrylamide gels containing sodium dodecyl sulphate followed by fluorography revealed that one protein (mol.wt. approx. 90 000) was characteristic of region 1, four proteins (one of mol.wt. 54 000 and three of mol.wt. 20 000) were synthesized principally in regions 2-5, and one protein (mol.wt. 22 500) was produced mainly in regions 6, 7 and 8. 3. Castration for 14 days decreased incorporation of [35S]methionine into total protein to less than 10% of that in controls in all regions of the epididymis. However, testosterone treatment for a further period of 14 days restored protein synthesis to normal values in regions 6, 7 and 8, but not in region 1 or regions 2-5. In regions 2-5 the synthesis of three proteins of mol.wt. 20 000 declined after castration, but was not stimulated by exogenous testosterone. Since the 20 000-mol.wt. proteins were major tissue proteins, accounting for 16-25% of the total synthesized, they were used as markers for investigating hormone action in the epididymis. 4. Castration followed immediately by testosterone treatment or ligation of the ductuli efferentes resulted in a decrease in their synthesis, suggesting that they are partially dependent on factors in testicular fluid. Purification and characterization showed them to be acidic glycoproteins with a number of biochemical and immunological properties in common. 5. It is suggested that there is a synergistic action between blood androgens and factors in testicular fluid in regulating protein synthesis in the proximal regions of the rabbit epididymis.

Synthesis of androgen-dependent secretory proteins by rat seminal vesicles

Androgenic steroids control the synthesis and secretion of several proteins by the seminal vesicles of the male rat. Prominent among them are 2 basic proteins, S and F, previously used as markers of androgen action. These proteins are not found among translation products of a wheat-germ protein-synthesising system supplied with mRNA from seminal vesicles of normal rats. Instead, higher molecular weight forms, S' and F', are formed which are nonetheless related antigenically to S and F respectively. Injected into Xenopus Laevis oocytes, seminal vesicle mRNA does direct synthesis and secretion of polypeptides S and F. Partial peptide analysis confirms that S' and F' have extensive amino acid sequence homology with S and F respectively. We conclude that S' and F' are precursor forms of the secreted proteins and thus at least 2 abundant proteins of this male accessory tissue are secreted by a mechanism common to a wide number of secreted proteins.

Developmental regulation of secretory protein synthesis in rat seminal vesicle

This paper reports a developmental study of one of the major secretory proteins (SVS IV) of the rat seminal vesicle. Measured by radioimmunoassay, SVS IV is detectable even in very young rats (5 days old) but does not begin to accumulate in massive amounts until animals reach about 35 days of age. We have compared SVS IV synthesis by minced tissue from rats undergoing sexual maturation (25-60 days of age) with levels of translatable SVS IV mRNA present. Between 25 and 60 days of age, the proportion of newly synthesized protein devoted to SVS IV by tissue minces increased from 0.8% to 20%. In contrast, the proportion of total RNA devoted to translatable SVS IV mRNA was already high in the immature glands and increased less than 4-fold during development. These results seem to indicate that factors other than the presence of potentially translatable message regulate the rate of net synthesis of SVS IV during seminal vesicle maturation.

The construction, identification and characterisation of plasmids containing human alpha-lactalbumin cDNA sequences

We describe the cloning of double-stranded cDNA synthesized from lactating human mammary gland total poly(A)-containing RNA, into the EcoRI site of the plasmid pAT153. Nine recombinants were shown to contain alpha-lactalbumin cDNA sequences as determined by positive hybridisation translation of complementary RNA. Restriction enzyme maps were determined for six of these. Alignment of the restriction map with the known amino acid sequence of human alpha-lactalbumin provided evidence that two plasmids, designated phO-53 and phB-35, contained the complete coding sequence of the primary translation product (pre-alpha-lactalbumin). Hybridisation studies using purified human, monkey and guinea-pig alpha-lactalbumin cDNA demonstrated that greater nucleotide sequence divergence has occurred within the rodents than the primates, and that rodent alpha-lactalbumin mRNAs retain regions of homology with primate alpha-lactalbumin mRNAs.

Problems associated with dose response in steroid-hormone activation of structural genes

A typical target cell for a sex steroid hormone contains 10 000--20 000 specific high-affinity receptors for that hormone. However full physiological responses can be achieved with only 2000 of these receptors involved in hormone--receptor complex interaction with the nucleus. The number of nuclear acceptor sites that must be filled before responses occur maybe even less. This implies that multiple occupation of nuclear acceptor sites by hormone--receptor may occur permitting co-operative induction of transcription of selected genes. The numbers of sites of initiation of RNA synthesis seem excessively high (about 70 000 per cell). Although this may be an artifact of the isolation procedures the proportion of initiation sites under hormonal control (equivalent to about 30 000 per cell) is still large. The numbers of mRNA species under hormonal control varies greatly depending on the particular hormone and target tissue. The extent to which these different observations can be incorporated into a unifying theory is discussed.

Androgenic regulation of messenger RNA in rat epididymis

1. The regulation by testosterone of mRNA complexity and mRNA activity was investigated in rat caput and cauda epididymidis. 2. The sequence complexity of cytoplasmic poly(A)-containing RNA from normal rats was determined by homologous hybridization with radiolabelled complementary DNA probes by using RNA in excess. Computer analysis of results suggested that hybridization could best be described by curves composed of two components distinguished by their relative abundance. Thus caput-epididymidal RNA consists of approx. 260 moderately abundant and 16400 scarce sequences, whereas cauda-epididymidal RNA consists of approx. 124 moderately abundant and 13400 scarce sequences. Judging by heterologous-hybridization reactions, castration did not result in appreciable alterations in either sequence complexity or the relative abundance of the two classes of poly(A)-containing RNA. 3. To investigate if individual mRNA sequences were regulated by androgens, mRNA was translated in a cell-free system derived from reticulocyte lysate. Since most of the translation products had a different mobility on sodium dodecyl sulphate/polyacrylamide gels from the authentic proteins synthesized in tissue minces, antibodies were used to identify specific translation products. Antibodies to the two related major proteins (mol.wt. 18500 and 19000) secreted by the caput epididymidis and whose synthesis is stimulated by testosterone both precipitated a single translation product of mol.wt. 21000. That this polypeptide was a precursor to the secreted proteins was suggested by the fact that the addition of microsomal membranes isolated from dog pancreas resulted in the appearance of a polypeptide of mol. wt. 19000. 4. Translation of RNA from the caput epididymidis of rats of different hormonal status showed that mRNA activity for the 21000-dalton polypeptide declined after castration, but could be restored by treating rats with testosterone. 5. It is concluded that testosterone stimulates the synthesis of a major protein secreted by the caput epididymidis by regulating its mRNA activity.

Differential distribution of poly(A)-containing RNA sequences between the nucleus and post-nuclear supernatant of the lactating guinea-pig mammary gland

RNA complexity analysis of poly(A)-containing RNA isolated from the lactating guinea-pig mammary gland demontrates that the complexity within the nuclear population was three--four-fold greater than that in the equivalent post-nuclear polyribosomal population [see Craig et al., Biochem. J. (1979) 181, 737-756]. Up to 21 000 different sequences distributed in two abundance groups were detected in the nucleus, whereas 5000 sequences distributed in three abundance groups were present in the post-nuclear population. All poly(A)-containing RNA sequences present in the post-nuclear fraction could be detected in the nuclear poly(A)-containing population. Analysis of the relative distribution of the three post-nuclear abundance populations within the nuclear poly(A)-containing RNA population demonstrates that the abundant and moderately abundant post-nuclear sequences were present a similar concentrations within the nucleus, and comprised the abundant nuclear population. The abundant and moderately abundant post-nuclear sequences were present at 62200 and 785 copies of each sequence/cell in the post-nuclear fraction respectively, and 44 and 118 copies of each sequence/cell in the nuclear fraction respectively. The scarce post-nuclear sequences (18.5 copies of each sequence/cell) were also present at low levels in the nuclear fraction (0.1 copy of each sequence/cell). the results are discussed in terms of the post-transcriptional regulation of gene expression in the lactating guinea-pig mammary gland.

In vitro translation of major abundant class poly(A+)-mRNA from rat seminal vesicle

Total poly (A)-containing messenger RNA [poly(A)-mRNAT] was isolated from seminal vesicles of adult male rats. By preparative 5%-20% linear sucrose gradient centrifugation in 1% SDS, a single peak was seen in the 11S region [poly(A)-mRNA11S]. Poly (A)-mRNAT and poly(A)-mRNA11S were translated in the wheat germ S-30 in vitro translation system. Laemmli-SDS-polyacrylamide slab gel electrophoresis of translation products of poly(A)-mRNAT revealed three major protein bands at approximately 18,500, 15,000, and 14,000 daltons. In vitro translation of poly(A)-mRNA11S across the 11S peak revealed partial purification of the mRNAs for the three predominant proteins. The lower molecular weight part of the 11S peak enriched for the mRNAs coding for the 15,000 and 14,000 dalton polypeptides, and the higher molecular weight side of the peak enriched for the 18,500 dalton mRNA. The highly abundant class of mRNA from rat seminal vesicle can be purified with one sucrose gradient centrifugation.

Androgenic regulation of messenger RNA sequence complexity in accessory sexual tissues of the male rat studied with fractionated complementary DNA

Effects of androgens on mRNA sequence complexity in the rat seminal vesicle have been investigated using complementary DNA fractionated on the basis of sequence abundance. Total cDNA complementary to poly(A)-rich RNA from normal rats was hybridised with an excess of the same RNA to controlled rot values and then the free cDNA was separated from cDNA . RNA hybrids by hydroxyapatite chromatography. Three cDNA fractions were obtained with very different hybridisation characteristics. Abundant cDNA hybridised to an excess of its parental RNA with an rot 1/2 of 2.46 x 10(-3) mol 1(-1) s and is complementary to about six or seven average-sized sequences. Use of hybrid-arrested translation in a cell-free protein-synthesising system has shown that this class of mRNA includes mRNAs coding for major androgen-dependent secretory proteins. Moderate and scarce cDNA fractions each showed more complex hybridization kinetics; computer analysis suggested each is complementary to two groups of average-sized sequences. Each cDNA fraction was hybridised to excess poly(A)-rich RNA from normal or castrated rats and the kinetics compared. Castration had no effect on the total number of sequences present in any class and did not alter the relative concentration of the scarce sequences. A small (threefold) decrease was seen in the concentration of abundant sequences with a larger (tenfold) decrease in the moderate class. Both de-reases were reversed by testosterone in vivo. The results are consistent with earlier studies where the effects of testosterone on seminal vesicle mRNA were followed using a translation assay and confirm that no gross differential effects are exerted on abundant mRNA coding for major secretory proteins. The cDNA fractions were also used to investigate the overlap in genetic expression between seminal vesicle and ventral prostate. Both tissues share all the scarce sequences in the same relative abundance. Less than 0.0015% and 0.004% of prostatic mRNA is complementary to seminal vesicle abundant and moderate sequences respectively. Similarly prostatic abundant sequences account for less than 0.004% of seminal vesicle mRNA.

Qualitative and quantitative changes in uterine mRNA populations in response to oestradiol treatment of rats

The mRNA population of immature rat uteri, responding to different lengths of oestradiol-induced differentiation, have been compared by the technique of DNA hybridization with heterogeneous RNA. Over the first 4 h of hormone induction there are continuing qualitative and quantitative changes in the poly(A)-containing mRNA such that, by 4 h after oestradiol administration, the population bears little resemblance to that of the unstimulated animal. Between 2 h and 4 h after oestradiol administration, the most striking changes appear to be in sequences of intermediate abundance. The possible significance of these findings is discussed.