Abbreviations and Conventions

Instructions to Authors (PDF)

Abbreviations

General. Abbreviations should be used as an aid to the reader, rather than as a convenience for the author, and therefore their use should be limited. Abbreviations other than those recommended by the IUPAC-IUB (Biochemical Nomenclature and Related Documents, 1992) should be used only when a case can be made for necessity, such as in tables and figures.

It is often possible to use pronouns or to paraphrase a long word after its first use (e.g., “the drug” or “the substrate”). Standard chemical symbols and trivial names or their symbols (folate, Ala, Leu, etc.) may also be used.

Define each abbreviation and introduce it in parentheses the first time it is used; e.g., “cultures were grown in Eagle minimal essential medium (MEM).” Generally, eliminate abbreviations that are not used at least three times in the text (including tables and figure legends).

Not requiring introduction. In addition to abbreviations for Système International d’Unités (SI) units of measurement, other common units (e.g., bp, kb, and Da), and chemical symbols for the elements, the following should be used without definition in the title, abstract, text, figure legends, and tables:

  • DNA (deoxyribonucleic acid)
  • cDNA (complementary DNA)
  • RNA (ribonucleic acid)
  • cRNA (complementary RNA)
  • RNase (ribonuclease)
  • DNase (deoxyribonuclease)
  • rRNA (ribosomal RNA)
  • mRNA (messenger RNA)
  • tRNA (transfer RNA)
  • AMP, ADP, ATP, dAMP, ddATP, and GTP, etc. (for the respective 5′ phosphates of adenosine and other nucleosides) (add 2′-, 3′-, or 5′- when needed for contrast)
  • ATPase and dGTPase, etc.(adenosine triphosphatase and deoxyguanosine triphosphatase, etc.)
  • NAD (nicotinamide adenine dinucleotide)
  • NAD+ (nicotinamide adenine dinucleotide, oxidized)
  • NADH (nicotinamide adenine dinucleotide, reduced)
  • NADP (nicotinamide adenine dinucleotide phosphate)
  • NADPH (nicotinamide adenine dinucleotide phosphate, reduced)
  • NADP+ (nicotinamide adenine dinucleotide phosphate, oxidized)
  • poly(A) and poly(dT), etc. (polyadenylic acid and polydeoxythymidylic acid, etc.)
  • oligo(dT), etc. (oligodeoxythymidylic acid, etc.)
  • UV (ultraviolet)
  • PFU (plaque-forming units)
  • CFU (colony-forming units)
  • MIC (minimal inhibitory concentration)
  • Tris [tris(hydroxymethyl)aminomethane]
  • DEAE (diethylaminoethyl)
  • EDTA (ethylenediaminetetraacetic acid)
  • EGTA [ethylene glycol-bis(β-aminoethyl ether)-N,N,N′,N′-tetraacetic acid]
  • HEPES (N-2-hydroxyethylpiperazine-N′-2-ethanesulfonic acid)
  • PCR (polymerase chain reaction)
  • AIDS (acquired immunodeficiency syndrome).

Abbreviations for cell lines (e.g., HeLa) also need not be defined.

The following abbreviations should be used without definition in tables:

  • amt (amount)
  • approx (approximately)
  • avg (average)
  • concn (concentration)
  • diam (diameter)
  • expt (experiment)
  • exptl (experimental)
  • ht (height)
  • mo (month)
  • mol wt (molecular weight)
  • no. (number)
  • prepn (preparation)
  • SD (standard deviation)
  • SE (standard error)
  • SEM (standard error of the mean)
  • sp act (specific activity)
  • sp gr (specific gravity)
  • temp (temperature)
  • vol (volume)
  • vs (versus)
  • wk (week)
  • wt (weight)
  • yr (year)

Reporting Numerical Data

Standard metric units are used for reporting length, weight, and volume. For these units and for molarity, use the prefixes m, μ, n, and p for 10−3, 10−6, 10−9, and 10−12, respectively. Likewise, use the prefixes c for 10−2 and k for 103. Avoid compound prefixes such as mµ or µµ. Use µg/ml or µg/g in place of the ambiguous ppm. Units of temperature are presented as follows: 37°C or 324 K.

When fractions are used to express quantities such as enzymatic activities, it is preferable to use whole units, such as “g” or “min,” in the denominator instead of fractional or multiple units, such as µg or 10 min. For example, “pmol/min” is preferable to “nmol/10 min,” and “μmol/g” is preferable to “nmol/μg.” It is also preferable that an unambiguous form, such as exponential notation, be used; for example, “μmol g−1 min−1” is preferable to “μmol/g/min.” Always report numerical data in the appropriate SI units.

For a review of basic statistical considerations for virology experiments, see the article by Richardson and Overbaugh (J Virol 79:669-676, 2005).