Science Books

V. J. Birstein Cytogenetic and Molecular Aspects of Vertebrate Evolution

В. Я. Бирштейн. Цитогенетические и молекулярные аспекты эволюции позвоночных (in Russian), Moscow: Nauka (Publishing House of the Soviet Academy of Sciences), 1987. 285 pp.,

(a rough translation of this book into English under the title Birstein, V. J. Vertebrate Evolution: Karyotypes, Chromosomes, and Genomes. 200 pp. is available at the Smithsonian Institution Library, Washington, D.C.; call number: QL607.5.B56 1991a)

Review of the book in Genetika (Genetics):

A huge coverage of data allows the author to make a number of phenomenological generalizations regarding the karyotypic macroevolution. […] The material allows [him] to give the current explanation of the so-called C-paradox of the DNA content. […] The author pays special attention to the fraction of mid-repetitive DNA sequences that includes genetic mobile elements. […] Precisely the G-segments of chromosomes, where the DNA sequences similar to mobile elements are located, are responsible, according to the author’s hypothesis, for the “architecture” of chromosomes and genomes [in the cell nuclei]. They stabilize syntenic groups of genes and are responsible for the attachment of chromosomal segments to the nucleus membrane and matrix. […]

Without doubt, the book by V. J. Birstein will be extremely useful for researchers interested in the problems of cytogenetics and evolution, and it is absolutely needed for current understanding of trends in genome changes during the scores of millions of years of vertebrate evolution.  

—M. D. Golubovsky. 1989. “Review of the book V. Ya. Birstein. Cytogenetic and Molecular Aspects of Vertebrate Evolution (Moscow: Nauka Publ., 1987). 285 pp.,” Genetika [Genetics], v. 25, no. 3: 569-570 (in Russian). 

Synopsis. This is a comparative review of data on karyotypes, DNA content and genome structure in all classes of vertebrates, from the lower vertebrates and fishes to mammals (1.354 papers and books were included in the review). Evolutionary trends are described in the context of changes in the genome, chromosome and chromatin structure in various vertebrate classes. The book focuses on a description of the difference in the longitudinal organization of chromosomes in fishes and amphibians contrary to  all higher vertebrates (amniotes). Taking into consideration this difference, a possible difference in the organization of interphase chromosomes in the nuclei of amphibians and mammals is discussed. This difference might have been caused by an inclusion and then redistribution of particular AT-rich mobile elements throughout the genomes of ancestral amniotes which resulted in the creation of a compact chromatin structure in the chromosomes of amniotes, which can be detected as G-bands during differential staining. In conclusion, principal karyotype and genome structure reorganizations that occurred in the vertebrate phyletic line are discussed as steps of vertebrate evolution.

Contents

This book would not have been written without influence of my father, Jacob A. Birstein, a zoologist and evolutionist, from whom I heard the word “evolution” for the first time in my life.

Introduction

Chapter I. Trends in Karyotypic and DNA Content Evolution

1. Lower Chordates (Tunicata and Acrania) and Cyclostomata

2. Fishes

2.1. Chondrichthyans 

2.2. Chondrostei and Holostei

2.3. Brachiopterygii, Sarcopterygii, and Teleostei

3. Amphibians

3.1. Apoda

3.2. Gymnophions

3.3. Anurans

3.3.1. Archaeobatrachians

3.3.2. Neobatrachians

3.4. General Comments and Possible Karyotype of Ancestral Vertebrates

4. Reptilians

4.1. Turtles (Chelonia)

4.2. Phynchocephalia and Crocodylia

4.3. Squamata

4.3.1. Lizards (Sauria)

4.3.2. Amphisbaenia

4.3.3. Snakes (Ophidia)

4.4. General Considerations

5. Birds (Aves)

6. Mammals (Mammalia)

6.1. Monotermata

6.2. Metatheria and Eutheria

7. General Comments (and Possible Therian Ancestral Karyotypes)

Chapter II. Differential Staining of Vertebrate Chromosomes

1. Teleosts

2. Amphibians

3. Reptiles

4. Birds

5. Mammals

5.1. Main Patterns in Distribution of G- and C-Bands

5.2. G-Banding Pattern and Gene Location

5.3. Differential Staining and DNA Content

6. General Considerations

Chapter III. DNA and Genome Organization in Vertebrates

1. Lower Vertebrates and Fishes

2. Amphibians

3. Reptiles

4. Birds

5. Mammals

5.1. General Characteristics of Genomes

5.2. Satellite DNA and Speciation

6. Mobile Dispersed DNA Sequences

7. Sex Specific DNA and Differentiation of Sex Chromosomes

8. Ribosomal RNA Genes

9. Main Trends in Vertebrate Genome Evolution

Chapter IV. Longitudinal Differentiation of Chromosomal Structure

In Vertebrates and the Interphase Nucleus

1. G-Bands: The Structure and Mechanism of G-Banding

2. Mechanism of Q-Staining

3. Characteristics of C-Stained Chromosome Regions

4. Chromosome Structure in Mammals

5. Amphibian Chromosomes

6. Chromosomes in the Interphase Nucleus

Conclusions: Karyotypic and Genome Structure Reorganization Events in Vertebrates as Evolutionary Stages

References

Index of Genera Names

Excerpt from Conclusions:

On the basis of a comparative revision of the cytogenetic, genetic, and molecular data it is concluded that there was a succession of principal changes in the structure of genetic material during the vertebrate evolution. These changes included rearrangements in the structure of genomes, individual chromosomes, and the whole karyotypes. Changes in the size of the unique DNA sequences fraction, in the ratio of fractions of the unique and repetitive DNA sequences, in the internal structure and shape of chromosomes, as well as in the longitudinal compartmentalization of chromatin within chromosomes occurred. These processes did not take place simultaneously. Changes in the genome size and a relative content of fractions within a genome were not accompanied by chromosome rearrangements, but often preceded them, while the chromosome rearrangements sometimes caused changes in the content of some of the genome fractions. In general, there were at least five stages of principal reorganizations of the genetic material in the course of vertebrate evolution, which could be called macroevolutionary events.

Most likely, at the level of protochordates a “minimal” size of the unique DNA fraction which is characteristic for all vertebrates was obtained. Karyotypes of the most primitive tunicates consist of approximately 40 small chromosomes, while in the Balanoglossus claviger (Hemichordata) karyotype there are 46 chromosomes, while the karyotypes of acranians consist of 32-38 chromosomes. In the meantime, the DNA content per nuclei in the tunicates is between 0.3-0.7 pg, in Balanoglossus, 1.0 pg, and in cyclosomes, 2.6-5.6 pg. It is hard to say if the formation of the ancestral genome of lower vertebrates was accompanied by a stabilization of a certain type of chromosome structure. It is also unknown if the chromosome structure of the protochordates, cyclostomes, and chondrichthyans is identical. The chromosome structure in the chondrichthyans seems to be very flexible because the genome size — all three main genome fractions of highly repetitive, mid-repetitive and non-repetitive (unique) DNA sequences — can grow without a significant or visible change in the chromosome morphology.

Apparently, the chondrichthyans were the first class of vertebrates in which very small chromosomes, called microchromosomes, started merging into the “typical” large macrochromosomes. This is evident from the fact that in most of the chondrichthyan species karyotypes consist of numerous large macrochromosomes and a number of small microchromosomes, but in all advanced forms of this class the number of microchromosomes reduces (sometimes they are even absent), while the number of macrochromosome increases.

The fusion of micro- into macrochromosomoses should have been an important stage of the chromosome structural reorganization in vertebrates because the length of chromatin in a macrochromosome is considerably longer than in a microchromosome. If microchromosomes, in fact, were fusing into macrochromosomes, the longitudinal structure of these two types of chromosomes should also differ, — for instance, there should be “silent” centromeres of mirochromosomes within the macrochromosomes.

However, microchromosomes are also present in the karyotypes of many, but not all of the most ancient representatives of phylogenetic branches of vertebrates, in the karyotypes of the Acipenseriformes (Chondrostei) and Lepisosteiformes (Holostei), in the oldest representatives of three amphibian orders, in ancient reptiles — chelonians, some lizards, snakes, and in almost all birds. Apparently, these so-called asymmetrical karyotypes were characteristic of all ancestral forms of terrestrial vertebrates and conservatively remained in the course of vertebrate evolution from chondrichthyans to reptiles and birds, which karyologically do not differ from reptiles.

The next step in the genome/cytogenetic evolution was the increase in size of both the unique DNA sequences fraction and the total DNA content in the ancestors of amphibians, especially in caudates.

In amphibians, with their typical development in two environments, in the water and on the land, the genome size is generally larger and varies more than in animals that develop and live in the same environment all their lives, such as chondrichtyans and fishes, on one hand, and most of reptiles, birds, and mammals (i.e. the group known as amniotes), on the other. Although the chromosome structure, judging from the results of differential staining, is similar in fishes and amphibians (it is not possible to reveal the so-called G- and R-segments in the chromosomes of these animals), the genome size in fishes generally varies less than in amphibians, and it is even more stable within each class of amniotes.

Apparently, an adaptation of the ancestral amphibians to the terrestrial life was accompanied by an increase in the genome size, and the development of these animals in two environments did not lead to a stabilization in the genome size. Most likely, in amphibians a molecular mechanism had evolved that allowed to quickly increase or decrease the amount of repetitive sequences within a genome and, as a consequence, to change the genome size.  

Evidently, in the cyclostomates, chondrichtyans, fishes and amphibians the process of polyploidization, i.e. reduplication of the whole chromosome set, played an important role in speciation and even in the origin of some new taxons like the acipenseriforms and teleosts. The ancestral forms of these taxons could have an ancient-type of karyotypes consisting of macro- and microchromosome (acipenseriforms), as well as the advanced, symmetrical karyotypes (teleosts).

During the next evolutionary phylogenetic step, the origin of the amniote ancestors, apparently the stabilization in the genome size, as well as a change in the ratio between the unique and repeated DNA sequences occurred.  Also, the ratio of the fractions of repetitive and unique sequences had changed, contrary to fishes and amphibians, the fraction of the unique sequences generally prevails in the genomes of amniotes.

But at this stage of the formation of ancestral reptiles a principal rearrangement in the chromosome structure also took place. Apparently, at this stage the longitudinal distribution of repetitive DNA sequences along chromosomes changed. This change might have been a result of obtaining and uneven redistribution of particular AT-rich “light” DNA elements in the genomes due to horizontal transposition.  These could be the LINEs-like DNA elements similar to the elements of the L1-family found in the genomes of vertebrates. The inclusion of such LINEs-like AT-rich sequences in the chromosomes and their redistribution along the chromosomes might have resulted in the compartmentalization of chromatin into the intra-chromosomal compact structures revealed as the G-bands, enriched in the LINEs elements, and prolonged regions between them revealed as the R-bands in the chromosomes of reptiles, birds, and mammals, but not in the chromosomes of fishes and amphibians. In fact, the intra-structural difference should also exist in the interphase chromosomes, but it could be revealed only in  differentially stained metaphase chromosomes. Obviously, this principle reconstruction in the intra-chromosomal structure in ancestral amniotes did not affect the basic syntenic groups of genes which remained almost unchanged from fishes to mammals.

All basic karyotypic changes in vertebrates that followed the change in the longitudinal chromosome structure of the ancestral amniotes, most probably, occurred in the course of evolution without a principal change in the internal compartmentalization of chromatin (the G- and R-regions) in chromosomes. Karyotype symmetrization that led to the formation of a karyotype typical for a group was the main process within the phylum after its branching from the main evolutionary stem. Possibly, at first the evolutionary rate of chromosome changes was high within each line of vertebrates, but then it became slower, and the “karyological stasis” had been achieved. The karyotypes continued to slowly evolve mostly through a reduction in the chromosome number via translocations of homologues of the smallest chromosome pairs to the other chromosomes of the sets, or, on the contrary, via polyploidization events (mostly in fishes and amphibians, but even in mammals, tetraploid species have been described).

Needless to say, the karyotypic symmetrization, i.e. formation of karyotypes consisting of only bi-armed chromosomes, occurred not in all ancient groups of vertebrates. Possibly, the direction in the karyotypic evolution depended on the environment in which representatives of a particular phyletic line existed. The crocodiles and birds that evolved from the same ancestral line of archosaurs are a good example of this trend. At the early evolution of crocodiles, the ancestral karyotype was reorganized, apparently fast, into a “typical” symmetrical karyotype consisting of bi-armed chromosomes. In birds, on the contrary, the “archaic” karyotype consisting of macro- and microchromosomes prevailed and, obviously, the rate of karyotypic evolution was constantly low. As a result, a paradoxical situation appeared: the birds, i.e., forms in which the “archaic” ancestral karyotype remained conserved, evolved into a separate class, while crocodiles, the forms with the “progressive” symmetric karyotypes , remained within the class of ancestral forms.

Apparently, mammals are the only class of vertebrates whose ancestors had a symmetrical karyotype consisting of only macrochromosomes. The Eutherians are characterized by a high karyological variability, a high karyotypic evolution rate, and a relatively stable genome size. A change in the genome size usually occurs due to a change in the content of the highly repetitive and unique DNA fractions, and not the middle repetitive DNA fraction like, for instance, in amphibians. On the whole, currently most of the phyletic lines are at the stage of intensive karyological evolution, when the “typical” karyotypes have not been formed yet. Such “typical” karyotypes have been formed in the metatherians and in the orders whose representatives live in the water environment, the Cetacea and Pinnipedia.  

Despite a high rate of karyological evolution in mammals, the data on the G-pattern and gene localization in chromosomes show that large segments of mammalian chromosomes remain unchanged during chromosomal rearrangements. Only the events of “karyological megaevolution”, when numerous chromosome rearrangements occur almost simultaneously, are exceptions to this general rule. An “explosion-like” release of mobile elements from chromosomes in generative cells before the meiosis, similar to that occurring in Drosophila, and the following random fusion of chromosomal segments can explain the mechanism of these “megaevolutionary” events. Since examples of chromosome rearrangements caused by transposons or retroviruses are known in mammals, this mechanism may play the main role in the “megaevolutionary” events.

Therefore, data on molecular and cytogenetic evolution in vertebrates point to the possibility that the longitudinal organization of chromatin had changed in the reptilian ancestors, i.e., in the ancestral amniotes, and this change might have caused a longitudinal restructuring in the metaphase chromosomes which could be revealed as the G- and R-bands after differential staining. Most likely, this reorganization occurred after a particular type of the AT-rich, possibly, LINES-like DNA elements had inserted into the genome(s) of ancestral amniotes. If these mobile elements amplified and then redistributed throughout the genomes of the ancestral amniotes, their new insertions might have led to the formation of compact structures that could be revealed during differential staining as the G-bands. This hypothetical process may have been an important stage in karyotypic evolution that, in its own turn, would have resulted in a change in the interphase chromosome organization. The presence of mobile elements in the genomes of amniotes might also cause the unusual “karyological megaevolutionary events” in mammals. 

St. Sergius and St. Bacchus, Byzantine iсon. 7th Century (Museum of Western and Oriental Art, Kiev, Ukraine). The study by V. Birstein confirmed that this icon was painted in an encaustic technique with the use of beeswax.

The Technology, Studies and Storage of Easel and Wall Paintings

В. Я. Бирштейн, В. П. Голиков, И. П. Горин, Ю. И. Гренберг и др.

Технология, исследование и хранение произведений станковой и настенной живописи (in Russian)

by V. J. Birstein, V. P. Golikov, I. P. Gorin, Yu. I. Grenberg et al., Moscow: Izobrazitelnoe iskusstvo, 1987. 400 pp.

Introduction

First Part. Basics of Technology of Easel and Wall Paintings

I. Introduction

II. Main Steps of Development of Painting Technology

1. Basis

2. Ground

3. Drawing

4. Paint Layer

5. Protective Layer

Second Part. Technological Study of Paintings

I. History of Development of Technological Study of Paintings

1. Main Stages

2. Methodological Basis of Studies

II. Non-Destructive Research Methods

1. Study in Visible Region of the Spectrum

2. Study in Ultraviolet

3. Study in Infrared

4. X-Ray Study

III. Studies of Samples

1. Study of Pigments and Mineral Components of Grounds

2. Light Microscopy

3. Microchemical Analysis of Non-Organic Materials of Paintings

4. Study of Plaster

5. Physical-Chemical Research Methods of Pigments (pages 182–185 written by V. Birstein)

6. Composition and Study of Organic Binding Media (pages 187–212 written by V. Birstein)

7. Chemical composition and Identification of Resins and Varnishes (pages 212–219 written by V. Birstein)

IV. Complex Studies of Art Works

1. Study of the Basis

2. Study of the Ground

3. Study of the Drawing

4. Study of the Paint Layer

5. Study of the Protective Layer

Third Part. Damages Caused by Biological Factors and Methods of Prevention

1. Bacteria

2. Microscopic Fungi

3. Insects

1. Carpenter Beetles

2. Termites

3. Flies

4. Methods of Precautions when Working with Pesticides

Fourth Part. Storage of Easel and Wall Paintings

1. Causes of Damage of  Paintings

2. Creation of Optimal Storage Regime

3. Treatment of Paintings

Appendices